You know it's a good party when no one wants to leave. While we had 16 remaining college football unbeatens at this point last season, we're holding steady at 22 in 2023. Only five fell in Week 5, and while we'll miss you, Duke, Georgia State, Kansas, Syracuse and Utah, the party continues.
Five of the remaining 22 teams are idle in Week 6, but things could still thin out a decent amount. We've got three unbeaten-versus-unbeaten matchups to look forward to -- Oklahoma-Texas, Kentucky-Georgia and Maryland-Ohio State -- and SP+ projects an average of 6.6 unbeatens to fall. But while this party is still together, let's do what we do: Let's rank them! Let's also discuss their biggest statistical strengths and weaknesses to date.
1.
Michigan Wolverines (5-0)
SP+ and FPI rankings: first and eighth
SP+ strength of schedule to date: 112th
What the Wolverines did in Week 5: def. Nebraska 45-7
Last week's ranking: 4
Biggest statistical strength: The most efficient defense in the country. It's nice to have that to fall back on, isn't it? The Wolverines rank first in success rate allowed (percentage of time an offense is gaining 50% of necessary yards on first down, 70% on second and 100% on third and fourth), first in points allowed per drive and, even once you've adjusted for a weak strength of schedule, second in defensive SP+. The moment you get the ball against them, you're behind schedule.
Biggest statistical weakness: We don't know what happens when they have to act with urgency. I guess that's less of a weakness and more of an absence of known strength. Still, the passing game hasn't been very aggressive (because it hasn't had to be), the big plays aren't particularly big and while the Wolverines have been great on third down, they're also waiting until third down a lot: Only 67% of their first downs have come on first or second down -- 67th in FBS and 17th among AP top-25 teams.
Next big test (next game with SP+ win probability at 75% or lower): Week 11 at Penn State.
2.
Ohio State Buckeyes (4-0)
SP+ and FPI rankings: second and first
SP+ strength of schedule to date: 42nd
What the Buckeyes did in Week 5: Idle
Last week's ranking: 3
Biggest statistical strength: Shockingly, it's big play prevention. Remember last year's Ohio State team? The one that fielded a wrecking ball of an offense and an aggressive defense that was far too all-or-nothing at times? This Ohio State isn't that Ohio State. The Buckeyes' defense currently ranks fourth in my marginal explosiveness measure (which looks at the magnitude of a team's successful plays and adjusts for down, distance and field position). They are sacrificing aggression for big-play prevention, and it's paid off thus far.
Biggest statistical weakness: They're losing the red zone. Of course, part of a good bend-don't-break approach is making stops when your opponent reaches the red zone. But the Buckeyes are currently 85th in red zone touchdown rate allowed (67%), and their offense is 96th (54%). It's really hard to remain among the unbeatens if you're settling for field goals and your opponent is scoring touchdowns.
Next big test: Week 8 vs. Penn State.
3.
Oregon Ducks (5-0)
SP+ and FPI rankings: sixth and sixth
SP+ strength of schedule to date: 109th
What the Ducks did in Week 5: def. Stanford 42-6
Last week's ranking: 5
Biggest statistical strength: Ruthless (and balanced) efficiency. They're third in overall success rate -- third rushing and fifth passing. They're first on standard downs (first downs, second-and-7 or less and third- or fourth-and-4 or less). Bo Nix is never pressured (first in pressure rate) and Oregon backs rarely move backwards (25th in stuff rate). This offense is always moving forward and never off-schedule. It's exhausting.
Biggest statistical weakness: An average run defense. The Ducks' pass defense has been impeccable, ranking first in yards allowed per dropback and 11th in sack rate. But they could struggle against opponents who can run. They rank 51st in rushing success rate allowed, and 49% of opponents' carries have gained at least four yards (97th). Quarterbacks have been particularly successful: Texas Tech's Tyler Shough rushed for 143 yards (not including sacks), and Stanford QBs rushed for 69.
Next big test: Week 7 at Washington.
4.
Washington Huskies (5-0)
SP+ and FPI rankings: seventh and ninth
SP+ strength of schedule to date: 90th
What the Huskies did in Week 5: def. Arizona 31-24
Last week's ranking: 1
Biggest statistical strength: Ruthless (unbalanced) efficiency. The Huskies rank first nationally in success rate, but while they're fourth in rushing success rate ... this team doesn't run the ball much. Their run rate is 12 percentage points below the national average on standard downs and 15 below on passing downs. Michael Penix Jr. is winging the ball around nonstop, and it works. Really, really well.
Biggest statistical weakness: No backfield invasion. A few alarm bells sounded late on Saturday night as the Huskies' defense allowed Arizona backup quarterback Noah Fifita to complete 27 of 39 passes, with only one sack, and lead four drives of 49 or more yards in a closer-than-expected 31-24 win. Washington still seems improved on D, but the Huskies rank 121st in stuff rate and 129th in sack rate. Those are dreadful disruption levels.
Next big test: Week 7 vs. Oregon.
5.
Georgia Bulldogs (5-0)
SP+ and FPI rankings: fourth and seventh
SP+ strength of schedule to date: 104th
What the Bulldogs did in Week 5: def. Auburn 27-20
Last week's ranking: 2
Biggest statistical strength: Good luck trying to pass on them. Injuries and slow starts have put the two-time defending national champs on the back foot more than expected, but the defense still looks mostly as you would expect. The Dawgs rank second in passing success rate allowed and eighth in yards allowed per dropback. Against the best offense they've faced, they held South Carolina's Spencer Rattler to 22 of 42 passing with three sacks and two interceptions.
Biggest statistical weakness: Slow starts and no big plays. Big plays create easy points, and Georgia ranks just 81st in marginal explosiveness (107th rushing, 71st passing). Combine that with some dreadful starts -- despite a soft schedule, the Dawgs' first-quarter scoring margin is +0.0 per game, worst of any team in the AP top 20 -- and you've got a team that has to work for quite a long time to get up on opponents as they should.
Next big test: Week 6 vs. Kentucky.
6.
Texas Longhorns (5-0)
SP+ and FPI rankings: third and fourth
SP+ strength of schedule to date: 32nd
What the Longhorns did in Week 5: def. Kansas 40-14
Last week's ranking: 6
Biggest statistical strength: Big plays from every direction. Only three teams in FBS have (a) made at least 30 gains of 20-plus yards and (b) averaged at least 35 yards per play in those gains. Xavier Worthy, Ja'Tavion Sanders and Adonai Mitchell have caught 15 combined passes of 20-plus, and Jonathan Brooks has four rushes of 40-plus, including two in Saturday's win over Kansas.
Biggest statistical weakness: They give you big plays, too. The Horns have only allowed 16 gains of 20-plus, which ranks a solid 29th nationally. But those 16 plays averaged 36.9 yards, 12th-most. Kansas hit them for gains of 45 and 58 yards, which kept the Jayhawks close into the second half.
Next big test: Week 6 vs. Oklahoma.
7.
Oklahoma Sooners (5-0)
SP+ and FPI rankings: ninth and second
SP+ strength of schedule to date: 96th
What the Sooners did in Week 5: def. Iowa State 50-20
Last week's ranking: 7
Biggest statistical strength: They can win in a lot of different ways. The last two games have been both enlightening and encouraging for Brent Venables' Sooners. Against Cincinnati in Week 3, the Sooner offense was scattershot, but the defense dominated in a 20-6 win. Against Iowa State on Saturday, the defense struggled early, but the Sooners gained 339 yards and scored 40 first-half points in a 50-20 win. They won a rock fight and a track meet.
Biggest statistical weakness: I'm not sure they can stop an explosive passing game. The Sooners have yet to face a top-40 offense (per SP+), but they rank 36th in yards allowed per dropback and 89th in passing marginal explosiveness. ISU completed touchdown passes of 67 and 51 yards last week, and, well, Texas' passing game is much better than ISU's.
Next big test: Week 6 vs. Texas.
8.
Penn State Nittany Lions (5-0)
SP+ and FPI rankings: 13th and fifth
SP+ strength of schedule to date: 79th
What the Nittany Lions did in Week 5: def. Northwestern 41-13
Last week's ranking: 8
Biggest statistical strength: Maybe the best pass defense in the country. The Nittany Lions have yet to face a top-60 offense, but they have thus far been unassailable: First in passing success rate allowed, second in yards allowed per dropback, first in raw QBR allowed, third in sack rate, ninth in pressure rate. The run defense is merely good, but if you have to throw, you're toast.
Biggest statistical weakness: Not nearly enough big plays. When you install a cannon-armed sophomore blue-chipper at QB, you might expect inconsistency and explosiveness. Penn State has gotten the opposite from Drew Allar. The Nittany Lions are 26th in success rate (excellent considering they've played against Iowa and two other good defenses), but they've managed five gains of 30-plus yards. Among power conference teams, only Minnesota has fewer.
Next big test: Week 8 at Ohio State.
9.
Florida State Seminoles (4-0)
SP+ and FPI rankings: 18th and 10th
SP+ strength of schedule to date: 18th
What the Seminoles did in Week 5: Idle
Last week's ranking: 9
Biggest statistical strength: Big plays and resilience. Only eight teams are averaging more than two gains per game of 40-plus yards. FSU is one of them. Johnny Wilson, Keon Coleman and Jaheim Bell are averaging 10.8 catches per game and 16.5 yards per catch between them. The Noles are patient, too: Eight of their nine huge gains came in the second half. Explosiveness drove comebacks against both LSU and Clemson.
Biggest statistical weakness: The run game isn't working. Trey Benson, Lawrance Toafili and Rodney Hill have averaged just 4.6 yards per carry with just two rushes of 20-plus yards. The Noles are a jarring 125th in rushing success rate. That puts so much on Jordan Travis' shoulders.
Next big test: Week 7 vs. Syracuse.
10.
USC Trojans (5-0)
SP+ and FPI rankings: 10th and 12th
SP+ strength of schedule to date: 124th
What the Trojans did in Week 5: def. Colorado 48-41
Last week's ranking: 10
Biggest statistical strength: The offense is still perfect. We rave and rave about Oregon and Washington (and justifiably so), but who's No. 1 in scoring offense? Who's No. 1 in offensive SP+? Caleb Williams and the Trojans. They remain the gold standard.
Biggest statistical weakness: The one good offense they faced scored 41. It's conceivable that the Trojans' defense has improved this year. They're 52nd in defensive SP+ (up from 87th last year) and 56th in points allowed per drive. But they've played one team ranked in the offensive SP+ top 50 (Colorado) and gave up 41 points. They faced two ranked between 50th and 100th and gave up 28 in each game. Even among the USC-Oregon-Washington trio of great offenses with potentially questionable defenses, they've got the worst defense of the bunch.
Next big test: Week 7 at Notre Dame.
11.
Miami Hurricanes (4-0)
SP+ and FPI rankings: 12th and 15th
SP+ strength of schedule to date: 67th
What the Hurricanes did in Week 5: Idle
Last week's ranking: 11
Biggest statistical strength: A weakness-free offense. Texas A&M is currently fourth in defensive SP+, and the Hurricanes hung 48 points on the Aggies. They've averaged at least 8.0 yards per play in every game. They're 13th in rushing success rate, seventh passing. They're 11th in marginal explosiveness. After last year's wretched showing (100th in offensive SP+), they still bear the burden of proof, but Miami's offense has been utterly brilliant so far.
Biggest statistical weakness: They give you third-and-manageables. Opponents are averaging 7.0 yards to go on third downs, 79th nationally, and they're converting 39% (65th). A particularly efficient opponent could play keep-away with the Miami offense.
Next big test: Week 7 vs. North Carolina.
12.
Kentucky Wildcats (5-0)
SP+ and FPI rankings: 21st and 31st
SP+ strength of schedule to date: 110th
What the Wildcats did in Week 5: def. Florida 33-14
Last week's ranking: 17
Biggest statistical strength: They make big plays, and you don't. They rank fourth in marginal explosiveness on offense and ninth on defense. They've ripped off 16 gains of 30-plus yards (16th) and allowed five (seventh). We're used to Mark Stoops' Wildcats being a pretty burly and physical squad, but this team has afterburners too.
Biggest statistical weakness: They're always behind schedule. When you're inefficient and reliant on big plays, that can render you inconsistent and unpredictable. Kentucky scored more on Florida than Eastern Kentucky, and a big factor in that is that they rank 82nd in success rate. Average third down distance: 8.2 yards (123rd).
Next big test: Week 6 at Georgia.
13.
North Carolina Tar Heels (4-0)
SP+ and FPI rankings: 23rd and 21st
SP+ strength of schedule to date: 72nd
What the Tar Heels did in Week 5: Idle
Last week's ranking: 14
Biggest statistical strength: The ball doesn't hit the ground. Drake Maye is completing 73% of his passes. Big sophomore running back Omarion Hampton is on pace for well over 1,000 rushing yards. North Carolina can beat you with the run or the pass, and they can utilize tempo effectively. They're good in the red zone too.
Biggest statistical weakness: They might have the worst run defense of any team on this list. UNC is up to 48th in defensive SP+ after finishing 90th and 70th, respectively, the last two seasons. But most of that is because of a solid pass defense. The Heels rank 95th in rushing success rate allowed and 83rd in stuff rate.
Next big test: Week 6 vs. Syracuse.
14.
Washington State Cougars (4-0)
SP+ and FPI rankings: 20th and 38th
SP+ strength of schedule to date: 40th
What the Cougars did in Week 5: Idle
Last week's ranking: 18
Biggest statistical strength: Ridiculous pass efficiency. It's almost a shame that there's so much great quarterbacking in the Pac-12 because Cameron Ward deserves heaps of love. He's on pace for 4,500 yards and 40 touchdowns, and despite heavy passing volume, the Cougs rank 11th in passing success rate and eighth in yards per dropback.
Biggest statistical weakness: Okay, maybe this is the worst run defense. They're 93rd in rushing success rate allowed and 120th in stuff rate. As with UNC, the pass defense is solid, but if you can run the ball, they might not be able to do anything about it.
Next big test: Week 6 at UCLA.
15.
Louisville Cardinals (5-0)
SP+ and FPI rankings: 29th and 27th
SP+ strength of schedule to date: 117th
What the Cardinals did in Week 5: def. NC State 13-10
Last week's ranking: 16
Biggest statistical strength: Epic explosiveness. Against Georgia Tech and Boston College, they mixed three rushes of 30-plus yards with eight such passes. Indiana and NC State defended them well but still got hit for a couple of big ones. Louisville is inconsistent but capable of scoring from anywhere on the field on any play.
Biggest statistical weakness: You make big plays against them too. Among unbeatens, only Florida State, USC and JMU have given up more gains of 30-plus. In marginal explosiveness, the Cards rank 10th on offense but 105th on defense. They give away a lot of the gains they create.
Next big test: Week 6 vs. Notre Dame.
16.
Missouri Tigers (5-0)
SP+ and FPI rankings: 27th and 35th
SP+ strength of schedule to date: 76th
What the Tigers did in Week 5: def. Vanderbilt 38-21
Last week's ranking: 19
Biggest statistical strength: The passing game just suddenly became amazing. Over the last three games, Brady Cook is averaging 364 passing yards per game at 10.1 yards per dropback. Luther Burden III is on pace for nearly 1,700 receiving yards, and transfer Theo Wease is coming off of his first 100-yard game in black and gold, too.
Biggest statistical weakness: The pass defense is less than the sum of its parts. Corner Kris Abrams-Draine is allowing a QBR of 0.3 with three picks. The secondary is one of the nation's most experienced, too. But the Tigers rank just 52nd in yards allowed per dropback and 101st in completion rate allowed. That's scary with Jayden Daniels and LSU coming to town.
Next big test: Week 6 vs. LSU.
17.
Maryland Terrapins (5-0)
SP+ and FPI rankings: 31st and 25th
SP+ strength of schedule to date: 125th
What the Terrapins did in Week 5: def. Indiana 44-17
Last week's ranking: 21
Biggest statistical strength: Maximum field tilting. Turnovers, offensive efficiency and good punting have given Maryland a massive field position advantage: The Terps are sixth in average starting field position (34.6) and seventh in field position allowed (25.2). Combine that with excellent big-play prevention, and you have to make a lot of good plays to score on them.
Biggest statistical weakness: OK, this is the worst run defense. They're 105th in rushing success rate allowed and 110th in stuff rate. It hasn't cost them yet, but they haven't played a top-80 offense yet, either. Ohio State might not have to ever throw the ball this coming Saturday.
Next big test: Week 6 at Ohio State.
18.
Air Force Falcons (5-0)
SP+ and FPI rankings: 37th and 47th
SP+ strength of schedule to date: 132nd
What the Falcons did in Week 5: def. San Diego State 49-10
Last week's ranking: 22
Biggest statistical strength: Death by a thousand cuts. The Falcons are as relentless as ever with their option attack, and they're as good as ever at it, too: They rank sixth in success rate, sixth in three-and-out rate and, once they approach your end zone, second in red zone touchdown rate. Their defense is brilliant in the big-play prevention realm, too. They force you to be as patient as they are.
Biggest statistical weakness: Option limitations. They're second in success rate on standard downs ... and 61st on passing downs. More than 11% of their dropbacks result in sacks. If you can't knock them off schedule, you can't win, but once you do, you can't lose.
Next big test: Week 13 at Boise State.
19.
Fresno State Bulldogs (5-0)
SP+ and FPI rankings: 42nd and 48th
SP+ strength of schedule to date: 130th
What the Bulldogs did in Week 5: def. Nevada 27-9
Last week's ranking: 23
Biggest statistical strength: This defense is increasingly nasty. The Bulldogs force three-and-outs 45% of the time (sixth). They're 23rd in rushing success rate allowed and 16th in yards allowed per dropback. They've allowed 19 total points in the last three weeks, and with only one top-70 offense remaining on the schedule, their numbers could get even gaudier.
Biggest statistical weakness: Their offense is ... backward. The Bulldogs get their efficiency but few big plays from the passing game and some big plays (but no efficiency) from the run game. That's not the way that usually works, and it's made their scoring pretty inconsistent.
Next big test: Week 6 at Wyoming.
20.
Liberty Flames (4-0)
SP+ and FPI rankings: 44th and 57th
SP+ strength of schedule to date: 133rd
What the Flames did in Week 5: Idle
Last week's ranking: 24
Biggest statistical strength: This is a Jamey Chadwell offense. Nobody does "option concepts mixed with modern and devastating passing" better than Chadwell, and his offense has immediately clicked at LU. The Flames are 24th in success rate and 19th in marginal explosiveness, and quarterback Kaidon Salter isn't that far from a pace of 3,000 passing yards and 1,000 rushing yards.
Biggest statistical weakness: Yeah, no, this is the worst run defense. They're 108th in rushing success rate allowed, and they haven't faced a top-80 offense yet. Granted, the schedule doesn't really get any harder moving forward.
Next big test: Week 7 at Jacksonville State.
21.
James Madison Dukes (5-0)
SP+ and FPI rankings: 55th and 76th
SP+ strength of schedule to date: 115th
What the Dukes did in Week 5: def. South Alabama 31-23
Last week's ranking: 25
Biggest statistical strength: You're always in third-and-long against them. The Dukes are fourth in rushing success rate, 12th on standard downs. It feels like you're immediately behind schedule when you get the ball, and their pass rush (seventh in sack rate) tees off on you, too.
Biggest statistical weakness: The run game hasn't clicked. Offensive coordinator Mike Shanahan (not that one) deploys a run-first attack, but Kaelon Black and Ty Son Lawton are averaging 4.9 yards per carry, and JMU ranks 102nd in rushing success rate. As a result, they rank only 86th in points per drive. That puts a lot of pressure on that awesome defense.
Next big test: Week 7 vs. Georgia Southern.
22.
Marshall Thundering Herd (4-0)
SP+ and FPI rankings: 63rd and 62nd
SP+ strength of schedule to date: 120th
What the Thundering Herd did in Week 5: def. Old Dominion 41-35
Last week's ranking: 27
Biggest statistical strength: An absolutely nasty pass defense. The Herd rank third in yards per dropback and seventh in passing success rate. Only 40% of completions they allow go for first downs (sixth), and only 5% go for 20-plus yards (second). They render you one-dimensional, only they're efficient against the run, too.
Biggest statistical weakness: This offense only sort of works. Like Fresno State, Marshall is dreadfully inefficient on the ground (124th in rushing success rate) and ultra-efficient through the air (18th in passing success rate). But any big plays they get probably come from running back Rasheen Ali. It's a bit of a mess, and they rank just 93rd in points per drive.
Next big test: Week 6 at NC State.