Probably Brady, but perhaps Brees
It is a record, as Drew Brees noted two years ago, that deserves a lot of respect. Dan Marino's single-season passing record of 5,084 yards has stood for 24 seasons, a testament to just how special Marino's 1984 performance as a second-year quarterback really was.
In 2008, Brees came within 15 yards of matching Marino's mark. This season, someone will top it. The bet here is that it will be Tom Brady.
The NFL has morphed into a passing league in recent years, and the numbers quarterbacks have put up through the first two weeks of this season are sick. Seven quarterbacks -- Brady, rookie Cam Newton, Philip Rivers, Brees, Tony Romo, Matt Hasselbeck and Aaron Rodgers -- are averaging north of 300 passing yards per game, the most ever at this point of a season. Of those seven, five are on pace for more than 5,400 yards, remarkable considering only two quarterbacks ever have reached the 5,000-yard plateau.
It is only Week 3. Newton will trail off. Romo and Hasselbeck probably will, too. But Rodgers, Brees, Rivers and Brady have the experience, arms and offensive weapons to stay on track. When the weather gets cold and blustery, things will get interesting.
Consider Brady. In two games, he has thrown for an NFL-record 940 yards. Only one player, Phil Simms in 1985, has ever thrown for more yards (945) in consecutive games.
Brady is on pace for 7,520 yards. He will never get there, of course, but if he averages 296 yards for the remaining 14 games, Brady will reach 5,084. That 296 is a workable number. In 2007, when New England went 16-0, Brady averaged 300.4 passing yards per game. On a frigid night in New York, he threw for 356 yards in the regular-season finale against the Giants and in December averaged 277.5 yards per game. He can do it again.
Brees could too. With 689 yards already, he needs to average 313.9 yards the rest of the way. In 2008, when he almost broke Marino's record, Brees averaged 316.8. And unlike Brady, who will play at Denver before ending the season with two games at Gillette Stadium, Brees plays at home in a dome.
After the 2008 season, Brees said this about breaking Marino's record: "It's meant to be won when you're going into the playoffs, when it's on a touchdown-winning drive."
Here's betting it will.
Ashley Fox covers the NFL for ESPN.com.
Even Brady can't beat weather
The zone that Tom Brady is in could let him break Dan Marino's 5,084-yard passing record by Thanksgiving, but I think he'll fall short.
The reason is weather. To achieve a 5,000-yard season, you need the perfect storm of weather conditions. Quarterbacks who play eight home games a year in a dome or in a warm-weather place such as Miami have the edge.
The weather in New England, along with the opportunities to rest Brady for the postseason, will leave him a few yards short. The same thing happened during his 50-touchdown season in 2007. In 2007, Brady was sitting at 4,095 yards with three games to go. To get Marino's record, a quarterback has to stay at a pace of 317.75 yards per game.
Brady had a game Dec. 16 against the Jets in which he threw for 140 yards. The next week he had a home game against the Dolphins and he had 215. His incredible season ended with 50 touchdowns and 4,806 yards.
In cold-weather stadiums, passing stats drop with the temperature, even for great quarterbacks like Brady. For his career, he's averaged 270.8 yards a game in September, 240.6 a game in October, 256 in November and 219.3 in December.
After the Oct. 23 bye, Brady and the Patriots are at the mercy of the elements in their remaining 10 games. They have trips to Pittsburgh, the New York Jets, the Philadelphia Eagles, the Washington Redskins and the Denver Broncos. Spread among those games are five home games.
It's unwise to say Brady won't be able to do something, but an injury or bad weather can throw everything off when going for a yardage record. In games in which the temperature is 40 degrees or lower, Brady throws for an average of 237.4 yards.
Another aspect to consider is the current state of the AFC. After you get past New England, the New York Jets, the Baltimore Ravens, the Pittsburgh Steelers, the San Diego Chargers and the Houston Texans, there is a huge gap. That's part of the reason Brady and the Patriots are off to such a great start.
If that trend continues, the Patriots could have a playoff spot wrapped up by early December, giving Bill Belichick the luxury of resting Brady and getting him ready for the playoffs.
Because they're on a playoff losing streak, Brady and Belichick will pay extra attention to making sure they can convert these great numbers into a trip to the Super Bowl. The yardage record is nice, but a Super Bowl ring is more important.
John Clayton, a recipient of the Pro Football Hall of Fame's McCann Award for distinguished reporting, is a senior writer for ESPN.com.