Back in 1960 -- not long before the start of the Super Bowl era -- Hall of Fame quarterback Johnny Unitas threw for 3,099 yards, marking the first time in NFL history a player cleared 3,000 yards in a single season.
Roughly 60 years later, we could soon see a quarterback double that mark.
As we enter the 2021 NFL season, 5,477 stands as the NFL single-season passing record, set in 2013 by a 37-year-old fellow named Peyton Williams Manning with the Denver Broncos.
Now that the league has added a 17th game, that record is in immediate jeopardy, and a previously unreachable target of 6,000 yards isn't out of the question.
"There's no doubt that that can happen," said former Miami Dolphins quarterback Dan Marino, the first to throw for 5,000 yards. "Guys are throwing for, what 5,300 yards? Two more games, you have a great year, you have a great time, you got players that are playing at a high level. That definitely can happen.
"If I was still younger with [receivers Mark] Duper and [Mark] Clayton, I would guarantee you 6,000. But I don't have to do it now. I don't have to prove it."
After Unitas hit 3,000, it took fellow Hall of Famer Joe Namath less than a decade to reach the next plateau, with 4,007 passing yards for the New York Jets in 1967. Then it was Marino with 5,084 yards in 1984. It took another 28 years before Drew Brees became the second to reach 5K. Overall, eight different quarterbacks have reached 5,000 -- with Brees doing it five times.
Manning appeared in all 16 of Denver's games during that 2013 season (he played 96% of the offensive snaps), which means he averaged 342.3 passing yards per game. Extrapolated over 17 games, that total jumps to 5,819 yards, which tells us it's not ridiculous to think a quarterback can reach 6,000 yards in the modern NFL.
"It can happen," said Kansas City Chiefs quarterback Patrick Mahomes. "You never know until you go out there and play."
Here is what a path to 6,000 passing yards looks like, as well as the most likely candidates to hit the mark in 2021.
The path
Here are six categories to a quarterback's path to 6,000 yards. All six boxes don't necessarily need to be checked, but the more that are, the more likely the mission will be accomplished.
1. Fast pace = lots of plays
Last season, the Los Angeles Chargers averaged a league-high 70.4 offensive snaps per game. The Houston Texans averaged a league-low 58.8 per game. Over a 17-game season, that works out to a difference of 197 plays, roughly 120 of which would be pass plays. At last season's league average of 6.81 yards per dropback, that works out to a potential gap of 817 passing yards. Yes, that's a lot.
One way to run a lot of plays is to operate a fast-paced offense, which is something we've seen more of in the league over the past decade. Consider that teams averaged 39.7 seconds between snaps in 2008 before dipping to 38.3 in 2014 and then settling in at 38.7 in 2020. The faster pace has led to more snaps (teams averaged 988 per season in 2008, compared to 1,028 in 2020). Obviously, an offense that moves quickly and runs a lot of plays can certainly boost a quarterback's quest for 6,000 yards.
Target: 66-plus snaps per game
2. Pass heavy
Despite the fact that Houston's offense ranked dead last in snaps per game last season, Deshaun Watson managed to lead the NFL in passing yards with 4,823. How? He checked off many other boxes, including operating in an offense that passed the ball a league-high 70% of the time. A pass-heavy offensive scheme helps a quarterback put up big yardage. Mahomes has finished second in passing yards in two of his three seasons as a starter while working in Andy Reid's pass-heavy scheme.
In 2019, Jameis Winston threw for a league-high 5,109 yards in Bruce Arians' pass-heavy scheme. In 2018, the Pittsburgh Steelers had the league's pass-heaviest offense and Ben Roethlisberger threw for a league-high 5,129 yards (yes, Big Ben, not Mahomes, led the NFL in passing during Mahomes MVP season). Tom Brady led the category in 2017 in a Patriots' offense that was pass heavy throughout his tenure. Brees' 80,358 passing yards are the most in league history and he benefited from a pass-heavy Sean Payton scheme during most of his time in New Orleans. Matt Ryan hasn't finished lower than sixth in passing yards since 2011 thanks to an Atlanta offense that is also very pass heavy. You get the point: call a lot of passes, get a lot of yardage.
Target: Team pass rate of at least 65%
3. Shaky defense
Calling a pass-heavy offense is one thing, but we know that playcalling is primarily driven by game script. If your team is ahead, you run more. If your team is behind, you throw more. And as the game progresses, the gap gets wider and wider. One way a quarterback can rack up extra yardage is by being forced to pick up the slack for a struggling defense. If your defense is really good, there is less pressure on your offense to move the ball and, in turn, pile up big passing yardage totals. If your defense is poor, your offense is more likely to be in catch-up or keep-up mode, and even if the efficiency is poor, the passing yardage totals are sure to rise.
The most straight-forward example is a quick look at the 2020 season. The teams that were passed on at the highest rate were the Buccaneers, Seahawks, Falcons, Ravens, Browns, Colts, Rams and Packers. Seven of those eight teams made the playoffs. The teams that were passed on at the lowest rate were the Jaguars, Cowboys, Texans, Lions, Eagles, Patriots, Vikings and Bengals. None of those eight teams made the playoffs. Defense is only half of the equation when it comes to game script, but a shaky one can obviously put more pressure on the quarterback to rack up yardage. In the quest for 6,000 yards, that's a good thing.
Target: At best, a midrange defense
4. High-end QB efficiency
Remember our earlier Watson example? In addition to benefiting from a pass-heavy offense and a poor defense, Watson posted a league-high yardage total last season thanks to elite efficiency. He ranked third in completion percentage (70%), second in yards per completion (12.6), first in yards per pass attempt (8.9) and fourth in average depth of throw (8.9).
A look at the highest single-season passing yardage totals over the past decade paints a pretty clear picture that quarterbacks must be in the vicinity of certain thresholds in order to have a shot at big numbers in the category. There were 10 instances in which a quarterback reached 5,000 yards during the stretch. Those quarterbacks averaged a 66.4 completion percentage (62.7% NFL average during the span), 8.1 yards per attempt (7.2), 12.2 yards per completion (11.5), 15% off-target rate (17%) and 4.4% sack rate (6.3%). Interestingly, average depth of throw (8.4 vs. 8.4 league average) and INT rate (2.4% vs. 2.5% average) didn't seem to matter much.
Target: Good-to-great showings in completion rate and YPA, while minimizing sacks.
5. Minimal to moderate scrambling
Perhaps the most impressive aspect of Watson leading the NFL in passing last season was he did it while also carrying the ball 90 times for 444 yards. Though that didn't prevent him from leading the league in passing yards, his rushing ability actually lowers his ceiling in that category and makes it unlikely that he'll ever crack 6,000.
Referring to our 5,000-plus-yard campaigns over the past decade, those quarterbacks averaged 34.1 carries and 93.9 rushing yards. In fact, in only two of those 10 seasons (Winston in 2019, Mahomes in 2018) the quarterback cleared 109 rushing yards, with an average of 52.1 yards in those other eight seasons. Rushing and scrambling ability is becoming more prevalent at the QB position, but logic and history tell us that the likes of Watson, Josh Allen, Kyler Murray, Lamar Jackson and Jalen Hurts will have trouble maxing out their passing yardage totals as long as they continue to pull the ball down and run so often.
Target: The lower the better, but a max of 50-60 carries
6. Elite health/playing time
This one is obvious, but any quarterback reaching 6,000 yards is going to need to avoid missing anything more than a handful of snaps. One game missed due to injury is one too many.
Another roadblock to hitting 6,000 would be late-game rest due to being on the delivery or receiving end of a blowout. Manning sat out the late stages of two games during his record-setting 2013 season, which is why he played 96% of the snaps, rather than the full 100%. The quarterbacks responsible for our 10 5,000-yard seasons averaged 676.3 dropbacks during those campaigns, with none falling below 606. Note that five quarterbacks (Ryan, Baker Mayfield, Watson, Kirk Cousins and Russell Wilson) were on the field for at least 98% of his team's offensive snaps in 2020, so holding up for a full 16-game season (let alone 17 games) is harder than it may appear.
Target: Snap percentage of at least 97%
Add it all up
Now that we have an idea of what it takes for a quarterback to throw for big-time yardage, we can essentially simulate these conditions and see if 6,000 yards is on the table.
Assuming:
A high-volume scheme (68 snaps per game would've ranked third in 2020)
Pass-heavy playcalling (67% pass rate, third)
A shaky defense (2.9 TDs allowed per game, 12th most)
Very good efficiency (8.5 YPA, 67% completion percentage)
Low-end scrambling (55 carries)
Good health (98% of dropbacks)
We would end up with the following 17-game stat line for "Player X":
472-of-707, 6,025 yards, 39 TDs, 13 INTs; 55 carries, 237 yards, 3 TDs
Mission accomplished. And we left some wiggle room in every category (believe it or not, 707 pass attempts is only second all time behind Matthew Stafford's 727 in 2012), so "Player X" could certainly check in lower in some areas and higher in others and still come away with 6,000-plus yards.
The top candidates
Now that we can see the path to 6,000, let's examine the top candidates to achieve the lofty feat in 2021.
1. Dak Prescott, Cowboys
Boxes checked: 6
You were expecting to see Mahomes here, weren't you? Let me explain. Prescott finished second in passing yards in 2019 (4,902) and was on a 17-game pace of 7,183 yards in four full games last season prior to suffering a season-ending ankle injury. Prescott has completed 66% of his career pass attempts (peaking at 68% in 2018 and 2020) and he has finished top-five in YPA in three of his five seasons (including 2019 and 2020). His 9.4-yard average depth of target (aDOT) in 2019 ranked fourth in the NFL. Prescott will benefit greatly from Mike McCarthy's offense. Dallas averaged 35.5 seconds between snaps (second fastest in 2020 and 12th over the past decade) and 1,109 offensive snaps (second, 11th) last season.
McCarthy has generally called a pass-heavy offense and was a bit above average in that department while Prescott was healthy last season. Prescott's ankle injury could be considered a red flag, but note he appeared in all 64 of Dallas' regular-season games during his first four NFL seasons, playing at least 98% of the snaps each season from 2017 to 2019. Prescott does pull the ball down and run at times, though he scrambled 20 times during his past full season in 2019, so this isn't a concern area. Dallas' offense -- led by Prescott, Amari Cooper, CeeDee Lamb, Michael Gallup, Ezekiel Elliott and a good (and now healthy) offensive line -- is loaded, but its defense is arguably among the bottom five in the NFL, which is good news in this scenario. Prescott is in his prime at age 28 and in a near-perfect situation to push for 6,000 yards.
Prescott on 6K: "I don't want to throw for 6,000 yards, to be honest with you. That means we're not running the ball. That means we're not probably doing the things we need to do to be a balanced, winning team. Sure, it would be great to have those numbers and to break that or to have that record or whatever it is. But it's not something that I put in my head. As I said, I want to be the best offense in the NFL, and I think the best way we can do that is if I'm not throwing that many yards and our run game is working and we're playing complementary football and we're winning a lot of games. And I think if that's the case, then hopefully I'm not playing as many fourth quarters trying to come back and do the two-minute drills we were doing in the first five games that got me a lot of those numbers [last year]."
2. Patrick Mahomes, Chiefs
Boxes checked: 5 (exception: pace of play)
If a sportsbook generated odds for the league's first 6,000-yard passer, my guess is Mahomes would be the favorite. The 25-year-old threw for 5,097 yards in his first full season as a starter in 2018. The former league and Super Bowl MVP benefits from an extremely pass-heavy offense (adjusted for game script, the Chiefs were the pass-heaviest team in the NFL last season) led by a coach who has called a pass-first offense in each of the past 12 seasons.
We know efficiency won't be an issue (career 8.4 YPA, 66% completion percentage) and Mahomes doesn't run enough to make us overly concerned (62 carries in 2020). Though pace of play is a slight issue, Mahomes makes up for it with the aforementioned efficiency, as the Chiefs' average of 6.48 plays per drive last season was the highest mark the league has seen since the Colts averaged the same in 2006. Mahomes would top this list if Reid's offense had more urgency (it finished below average in pace every season he has been with the team), but nonetheless, he's still one of the best bets to reach 6,000.
Mahomes on 6K: "It's going to be tough for a guy to get all the way to 6,000, but I'm sure guys will battle and I mean, the quarterback play that we have these days I'm sure at some point someone might be able to get there."
3. Tom Brady, Buccaneers
Boxes checked: 5 (exception: shaky defense)
Brady threw for 4,633 yards last season (third most in the league) while completing a healthy 66% of his passes. His 7.6 YPA isn't good enough, but an aggressive 8.9 aDOT gives him the opportunity for big plays. Tampa Bay hung around league average in pace and snaps last season, but big play totals are nothing new for Brady, as his Patriots ran 1,191 offensive plays in 2012 (highest the league has seen over the past decade) and 1,138 in 2013 (fourth most).
Durability isn't much of a concern (he hasn't missed a game due to injury in over a decade) and we know he won't pull the ball down and run (he hasn't cleared six scrambles in a season since 2016). Arians operates a pass-heavy scheme, and as such, Tampa Bay ran the league's game-script-adjusted fifth-heaviest passing offense last season. The main roadblock for Brady is a standout defense that returns all starters from 2020 and figures to limit the team's second-half shootouts. Adding to Brady's outlook is support from the league's best WR trio in Mike Evans, Chris Godwin and Antonio Brown (not to mention seam stretching tight end Rob Gronkowski). Brady hasn't reached 4,900 yards since he threw for 5,235 in 2011, but the 44-year-old is in one of the best positions for a run at 6,000.
4. Matthew Stafford, Rams
Boxes checked: 4 (exceptions: shaky defense, pass heavy)
Huge volume is nothing new for Stafford, who, as noted earlier, holds the NFL record for pass attempts in a single season with 727 in 2012. He threw for 4,967 yards that season, which was actually a step back from his 5,038 yards in 2011. Stafford hasn't cleared 4,500 yards over the past seven seasons, but the 33-year-old's situation has changed pretty drastically now that he's working with Sean McVay in Los Angeles.
McVay's offense moves at a rapid pace, ranking eighth in pace of play (37.8) and third in offensive snaps (1,087) last season. His offense ranked third in pace (36.9) and eighth in snaps (1,049) in 2019, so there seems to be a trend. McVay called a balanced offense last season, though he did lean slightly toward the pass (not quite "pass heavy") during the four prior seasons. Stafford has a history of good efficiency, completing at least 64% of his passes each of the past six seasons and peaking with an 8.6 YPA in 2019 (7.2 career YPA). Stafford has never cleared 26 scrambles in a single season and hasn't recorded 29 carries in a season since 2016, so we don't have to worry about lost volume there. The biggest red flag for Stafford is a Los Angeles defense that was best in the NFL last season. The unit lost coordinator Brandon Staley and several key players during the offseason, so a big step back is possible -- and necessary -- if Stafford wants to make a run at 6,000 yards.
Stafford on 6K: "Ahhh [slight chuckle], I don't even want to think about that number, that's crazy. Um, yeah, I'm sure somebody will, but I don't even know ... who led the, I mean, this is terrible I don't even know who led the league in passing last year, but yeah, I bet it will happen."
5. Aaron Rodgers, Packers
Boxes checked: 4 (exceptions: pace, defense)
Rodgers' career high in passing yards is 4,643, and that was set way back in 2011. Even during last season's MVP campaign, Rodgers threw for "only" 4,299 yards (ranking seventh) despite a career-high and league-best 70.7% completion percentage, as well as an 8.2 YPA (fourth). Durability (he has appeared in 16 regular-season games in six of the past seven seasons) and scrambling (max of 46 carries in each of the past four seasons) aren't concerns, but there are several detriments to Rodgers' outlook. They include a sloth-like offense that averaged 42.6 seconds between snaps last season (easily slowest in the NFL), which led to Green Bay's offense running 989 plays (sixth fewest).
Another roadblock is a good Green Bay defense that allowed only 39 touchdowns last season (eighth fewest) and remains strong on paper entering 2021. That more than offset Matt LaFleur's game-script-adjusted seventh-heaviest passing offense. Rodgers has the talent needed to reach the 6,000-yard milestone, but perhaps not the situation.
6. Justin Herbert, Chargers
Boxes checked: 4 (pace and playcalling are unknowns)
Looking for a sleeper to throw for 6,000 yards this season? Herbert is your guy. The 2020 sixth overall pick enjoyed one of the best seasons ever for a rookie quarterback last season. Despite sitting out Week 1, Herbert threw for 4,336 yards (ranking sixth) and ranked fourth in dropbacks, pass attempts and completions. His efficiency (67 completion percentage, 7.3 YPA) was good compared to the average NFL quarterback and elite by rookie QB standards. As noted earlier, the Chargers led the NFL in offensive snaps per game last season, and their total of 1,125 plays ranks eighth and their 6.44 offensive snaps per game fourth over the past decade. That's generally good news, but the Chargers ousted Anthony Lynn and replaced him with the defensive-minded Staley during the offseason. Staley comes from the high-volume McVay coaching tree, but it's unknown whether the Chargers will move at a fast pace and/or lean on a pass-heavy offense.
Herbert added some value with his legs as a rookie, though 55 carries (25 scrambles) isn't concerning. The Chargers' defense struggled last season and looks like a below-average unit on paper in 2021, though Staley's incredible work with the Rams' defense suggests the Chargers very well could overachieve in that department. Nonetheless, if Herbert proves to be the real deal, he can make a run at 6,000 if a few things go his way.
Herbert on 6K: "I think our whole goal this year is to win football games and whatever happens, happens."
Notable long shots: Wilson, Roethlisberger, Allen (if he cuts down on rushing), Joe Burrow and Ryan.
ESPN NFL Nation reporters Cameron Wolfe, Michael Rothstein, Todd Archer, Lindsey Thiry and Shelley Smith contributed to this story.