There's a three-headed quarterback battle going on in Washington, but right now journeyman veteran Case Keenum appears to be in the lead. This offseason, the Redskins sent a sixth-round pick to Denver in exchange for Keenum. That's a pretty low price, considering that Keenum was one of the best quarterbacks in the league just two years ago. The Redskins are hoping Keenum can duplicate his 2017 performance, when he led Minnesota to the playoffs. But that season stands out on Keenum's record as far superior to the rest of his career. It looks like a fluke.
Plenty of players have put up fluke seasons. But it's the quarterback flukes that stand out the most. Some of these players have bounced around from team to team, trying to recapture the magic of one great early season. Others come out of nowhere to have one huge season late in their career. If your team can't get a franchise quarterback, the next-best thing is to luck into lightning in a bottle by getting a veteran on the cheap and having him put up a big fluke year.
We've put together a list of the biggest fluke seasons by quarterbacks in Football Outsiders' play-by-play database, which goes back to 1986. This wasn't as simple as just taking the biggest difference between a quarterback's best year and his other years. We also considered how long each quarterback played as a starter and as a backup. For example, the player with the biggest difference between his best year and his second-best year, in both advanced stats (Football Outsiders' DYAR, or defense-adjusted yards above replacement) and standard stats (passing yards)? Patrick Mahomes, of course. But that's only two seasons, and in one of them Mahomes had just one start! Mahomes has plenty of time to prove he's not a young one-year wonder like Robert Griffin.
However, we start our biggest fluke year list with another current young star. Like Mahomes, he excelled in his first season as a starter. But he's fallen off that pace in the two years since.
10. Dak Prescott (2016 Dallas Cowboys)
On the surface, Prescott's three NFL seasons might not look that different from one another, but that's partly because an increase in attempts has kept his total stats somewhat stable. By advanced metrics, however, Prescott's second and third seasons have fallen far short of his rookie performance.
Prescott was fourth in the league in total value as a rookie (as judged by DYAR). In the two years since, he's fallen to 17th and then 25th. His QBR has fallen similarly, from 77.6 as a rookie to 69.9 and then 55.2 last year. Prescott is only 10th on this list because he's just three years into his career. He certainly could have another highly efficient season that rivals his rookie year. But so far, that first season sticks out as a clear exception on his statistical record.
9. Steve Beuerlein (1999 Carolina Panthers)
Beuerlein's 1999 season was a shock because it came from out of nowhere so late in his career, but it's more of a fluke based on standard stats than advanced metrics. At age 34, Beuerlein did have a couple of good seasons under his belt. He was ninth in DYAR with the 1993 Phoenix Cardinals and finished 15th in DYAR with the Panthers the year before. But at the start of 1999, Beuerlein still had to fend off former Denver backup Jeff Lewis in a camp battle for the starting spot.
Once he did that, he went on to have by far his greatest season. Beuerlein started 16 games for the first time and made his first Pro Bowl in his 13th season. He led the league with 4,436 passing yards, nearly 1,300 more than his previous career high. He threw 36 touchdown passes, double his previous career high. He achieved some of these big stats by throwing a lot of passes: 571, second in the league behind Brett Favre's 595. In Football Outsiders' advanced metrics, Beuerlein ended up fifth in passing DYAR for the season.
The following year, Beuerlein once again started all 16 games for Carolina, but his stats fell off by 700 yards and 17 touchdown passes. He was also sacked a league-leading 62 times in 2000. The next offseason, George Seifert cut Beuerlein, who spent his final three years in the NFL as the backup in Denver.
Beuerlein's big fluke season was also a big fluke season for one of his receivers. On one side, Beuerlein had a young Muhsin Muhammad. On the other side, he had a former Denver fifth-rounder named Patrick Jeffers. Jeffers had 1,082 receiving yards and 12 touchdowns. For the rest of his career, he managed just 481 yards and two touchdowns.
8. Don Majkowski (1989 Green Bay Packers)
Don Majkowski was a 10th-round pick back when the NFL draft had such things. In his first two seasons, he was in and out of the lineup as the Packers couldn't decide if they wanted to start Majkowski or Randy Wright. But the team finally cut Wright before the 1989 season and Majkowski took off. He led the Packers to a 10-6 record, their first winning season in over a decade. He led the league with 599 attempts and 4,318 yards. He also threw for 27 touchdowns, though he did have 20 interceptions, which is why he finished only eighth in Football Outsiders' DYAR metric.
Nonetheless, he looked like a promising young star. But by the time he got injured halfway through 1990, he had more interceptions than touchdowns. In 1991, he was benched because he somehow managed only three passing touchdowns in eight starts. An ankle injury ended his 1992 season after three starts, and he was replaced by Brett Favre. Majkowski went on to play four years as a backup in Indianapolis and Denver. When he had to play, he was lousy. For his career, 1989 was the only year of above-average efficiency, according to Football Outsiders' DVOA ratings.
7. Derek Anderson (2007 Cleveland Browns)
Anderson recently retired after a 14-year NFL career. In those 14 years, only once did he start at least 10 games: 2007, when he replaced Charlie Frye in the middle of a Week 1 loss. He went on to start the rest of the year and guided Cleveland to a 10-6 record. Anderson led the NFL with 12.7 yards per completion. He threw 29 touchdown passes -- 16 of them to Braylon Edwards -- and somehow took only 14 sacks.
In the offseason, Anderson signed a three-year contract to stay with the Browns, but he was benched halfway through the 2008 season after Cleveland started 3-5. He spent the next year and a half battling with Brady Quinn for the Browns' starting job when he wasn't battling injuries, then went to Arizona the next year and started nine games in which the Cardinals finished just 2-7. Over those three seasons, Anderson didn't even complete half his passes. The rest of his NFL career consisted of seven years as Cam Newton's backup in Carolina, followed by two starts after the Buffalo Bills dragged him off his couch last season.
6. Randall Cunningham (1998 Minnesota Vikings)
Not a lot of quarterbacks have their best season at age 35 after returning from a short-lived retirement. But of course, not a lot of quarterbacks get to play their age-35 season with Cris Carter and Randy Moss the way Cunningham did when the 1998 Vikings' offense took the league by storm.
Cunningham had been a Pro Bowler from 1988 through 1990, but his 1998 performance blew away anything he did in any of his other healthy seasons. Cunningham wasn't even supposed to be the starter, but he took over late in Week 2 after an injury to Brad Johnson and led the Vikings to a 13-1 record in his 14 starts. Compared to his other seasons with at least 10 starts, Cunningham had his highest completion rate (60.9%), his highest touchdown rate (8.0%) and his lowest interception rate (2.4%). He had over 8.0 net yards per pass attempt; he never got over 6.0 net yards per pass attempt in any of his other seasons with at least 10 starts.
The 1998 campaign was also a fluke year for Cunningham because of what he didn't do. In the other years in which he started at least 10 games, Cunningham always had at least 65 carries and multiple rushing touchdowns. In 1998, an older Cunningham carried the ball only 32 times and had just one rushing touchdown.
The next year, after the Vikings started just 2-4, Cunningham got benched in favor of Jeff George. He finished his career with two years as a backup in Dallas and Baltimore.
5. Nick Foles (2013 Philadelphia Eagles)
Nick Foles has had a very strange career. He's had five seasons with at least five games started but has never had a season with more than 11 games started. In almost every year, he's been the backup who had to play some.
It might seem odd to claim that 2013 was a fluke year when Foles led his team to a Super Bowl title in 2017. But when you look at Foles' regular seasons, the 2013 campaign stands out like a sore thumb, primarily because of two numbers: 27 and 2. As in, 27 touchdowns and only two interceptions. Foles also led the league with 9.1 yards per attempt and 14.2 yards per completion. His career highs in all his other seasons? Just 7.5 yards per attempt and 11.6 yards per completion.
By Football Outsiders' passing DVOA measure of efficiency, Foles was the No. 2 quarterback in 2013, behind only Peyton Manning and his record 55 touchdowns for the Broncos. In no other season has Foles ranked higher than 20th in passing DVOA. Last year, despite completing over 70 percent of his passes, he ranked just 25th.
4. Robert Griffin (2012 Washington Redskins)
Every fan knows the story of how Robert Griffin hurt his knee at the end of his rookie season, reinjured it in a playoff loss to Seattle and has never been the same quarterback since. But you might have forgotten just how good Griffin was as a rookie. He won the Offensive Rookie of the Year award over Andrew Luck and Russell Wilson.
By Football Outsiders numbers, Griffin's rookie year came in below Wilson's because Griffin played an easy schedule of opposing defenses while Wilson played a difficult schedule. But both quarterbacks finished in the top 10 in combined passing and rushing DYAR. Wilson has continued to play at a high level since his superb rookie season, but Griffin's game collapsed after he came back from the knee injury at the end of his rookie year. Not once since then has Griffin finished above replacement level by FO metrics.
3. Scott Mitchell (1995 Detroit Lions)
The conventional wisdom regarding Scott Mitchell goes like this: He played well in place of an injured Dan Marino for the Miami Dolphins in 1993. He hit free agency and signed a big contract with the Lions, and then he was horrible. He serves as a cautionary tale for any team that wants to sign the backup quarterback of a good offense and expects that quarterback to play just as well on another team.
Except that Scott Mitchell was not entirely horrible with the Lions. He was at first, completing less than 50 percent of his passes in 1994. But Mitchell had an absolutely fantastic season in 1995. He threw for more than 4,300 yards with 32 touchdown passes and only 12 interceptions. He added some hidden yardage as well: 260 extra yards on 16 defensive pass interference penalties. Overall, Mitchell finished second in Football Outsiders' DYAR metric, just ahead of Brett Favre and Troy Aikman and trailing only the Bears' Erik Kramer. (We'll get to him next.)
But after 1995, Mitchell was never again an above-average quarterback, according to DVOA. He spent three more years in Detroit, then bounced to Baltimore and Cincinnati as a backup.
2. Erik Kramer (1995 Chicago Bears)
Kramer had been one of Mitchell's predecessors in Detroit, a former CFL quarterback who spent a couple of years trading starts with Andre Ware and Rodney Peete. He signed with Chicago in 1994 and played at about replacement level for the Bears in five starts.
Then in 1995, he suddenly became one of the top quarterbacks in the league at age 31. He threw 29 touchdowns with just 10 interceptions. He threw for 3,838 yards, one of only two seasons in his career in which he threw for more than 2,000 yards. He was sacked only 15 times for the league's lowest sack rate. And he did all this against a tougher-than-average schedule. He finished first in Football Outsiders' DYAR metric, though he would have finished third behind Mitchell and Brett Favre without schedule adjustments.
But 1995 was the only year of Kramer's career in which he started all 16 games. Kramer missed most of the 1996 season with a neck injury. He started again for most of 1997 but ranked only 15th in passing DYAR that year, and Chicago was just 4-9 in his starts. He retired after another neck injury suffered while playing for San Diego in 1999.
1. Case Keenum (2017 Minnesota Vikings)
Not much was expected from Keenum as an undrafted free agent out of the University of Houston. And based on Football Outsiders' DVOA ratings, Keenum consistently came in below average while bouncing back and forth between the Texans' and Rams' rosters from 2012 to 2016. So not much was expected of Keenum when he replaced an injured Sam Bradford early in the 2017 season for the Vikings.
But with the help of a talented receiving corps led by Stefon Diggs and Adam Thielen, Keenum went on to have one of the best seasons of any quarterback in 2017. Keenum was 28.1% more efficient than average by DVOA, rating him as the most efficient quarterback in the league that season. Keenum had career bests in completion rate (by more than 5 percentage points), yards per attempt and touchdown rate.
That's the lightning in a bottle that Washington will try to recapture if they decide to start Keenum this season. It's the lightning that the Denver Broncos were unable to capture last season. Keenum fell from first in DVOA in 2017 to 28th last year. He threw for fewer average yards and fewer touchdowns with more interceptions and more sacks.
The 2017 season remains the only one in Case Keenum's career in which he put up an above-average passing performance, according to our metrics. The gap in DYAR between 2017 (1,293 DYAR) and his next-best year, 2015 (83 DYAR), is the largest for any quarterback in our database with at least three seasons played.