Predicting Tom Brady's Shelf Life Based on Careers of Other Great NFL QBs

If you believe Tom Brady, the New England Patriots quarterback is going to play "until they tell me they don't want me anymore."

If you believe his most trusted receiver, Wes Welker, Brady has at least another 10 years of playing left in him if he wants to.  

But does historical evidence of quarterbacks back the claims of either Brady or Welker? Could Brady play in the NFL until he's nearing 45 years old?

Or is the career of the now 35-year-old Brady closer to the finish line than either would like to admit?

While not every quarterback is created equal, it's worth taking a look at some of the more recent greats and how their career paths were shaped at the conclusion near the end:

Brett Favre (Falcons, Packers, Jets, Vikings)

Even the un-retireable Favre was pushed completely out of football by age 41.

He did give some memorable moments after the age of 35, however, leading both the Green Bay Packers (2007-08) and Minnesota Vikings (2009-10) to the doorstep of the Super Bowl. Late interceptions in both NFC title games kept Favre from appearing in his third Super Bowl.

Arguably his best ever season as a passer came in 2009, when the 40-year-old Favre threw 33 touchdowns against just seven interceptions as the Vikings won 12 regular-season games. 

Father Time eventually caught up. Favre's body began breaking down during his final year with the Vikings, and when combined with a 6-10 record in 2010-11, the decision became easy for Minnesota to let Favre walk. No NFL team has bit since. 

Favre has been "officially" retired for over a year.

Steve Young (Buccaneers, 49ers)
Troy Aikman (Cowboys)

Young and Aikman are clumped together for an obvious reason: Concussions drove each quarterback out of the NFL. 

Young was 38 years old when Aeneas Williams gave the 49ers quarterback his last head-related injury during Week 3 of the 1999 season. Young wouldn't return that season and eventually retired because of his long history of concussions. 

A year later, Aikman suffered numerous concussions and was forced to retire at the end of the 2000 season. Aikman was just 34 years old.

There's no conceivable way to discount the impact head-related injuries could have on the career of Brady. With concussion awareness at its all-time high in the NFL, a couple of dings upstairs could quickly change Brady's thinking on playing long-term.

Injuries to the head are obviously an uncontrollable part of the game, but it's still something to consider when etching the career path for Brady.

Dan Marino (Dolphins)

Marino played 17 long seasons in the NFL but hung up the cleats at the age of 38. The combination of injuries to his neck and legs and a 62-7 loss to the Jacksonville Jaguars during his final game helped push the Hall of Fame quarterback out of the game. 

However, another contributing factor—albeit, a smaller one—was the retirement of head coach Jimmy Johnson as the Dolphins coach. While unlikely, you have to consider the effect of head coach Bill Belichick on Brady's longevity, too. 

If Belichick were to retire or be let go (unlikely) as Patriots head coach in the near future, one could assume that Brady may not be as convinced to play into his 40s. The connection between Brady and Belichick seems to be one motivating factor for Brady's desire to play as long as he can. 

Brady told this to Peter King of Sports Illustrated:

"

I just met with coach Belichick this morning. I still feel like I'm in my first year trying to prove myself. There's no entitlement around coach Belichick. I've got to be the best guy for him to keep playing me. When I'm not, someone else will play.

"

Losing a coaching legend like Belichick in New England seems like a long-shot. But just as Brady told King, his spot atop of the depth chart won't always be etched in stone. If Brady's skill set regresses, Belichick hasn't been shy in the past about removing the well-liked veteran for a younger, better suited player.

Ask Bernie Kosar or Drew Bledsoe if you don't believe it.

Brady could eventually join that group if his passing skills erode in the coming years and/or 2011 draft pick Ryan Mallett emerges as Belichick's best option. 

Warren Moon (Edmonton Eskimoes, Oilers, Vikings, Seahawks, Chiefs)
Steve DeBerg (49ers, Broncos, Buccaneers, Chiefs, Dolphins, Falcons)
Vinny Testaverde (Buccaneers, Browns, Ravens, Jets, Cowboys, Patriots, Panthers)

Welker's claim that Brady could play another 10 years may not be as far-fetched as it seems. As long as Brady keeps his health, there are examples of quarterbacks lasting deep into their 40s at the professional level.

Moon played in the NFL until he was 44 years old, although he started just one game during his final two seasons. From 1997-99, however, Moon made 24 starts as a member of the Seattle Seahawks. He was 41 and 42, respectively, during those seasons. 

DeBerg took five seasons off from the NFL from 1993-98, but returned at age 44 to play in eight games for the Atlanta Falcons. He threw three touchdowns against just one interception but lost the one game he started for Atlanta during the 1998-99 season. 

Testaverde may be the very best role model for Brady, as the 44-year-old made six starts for the Carolina Panthers during his 21st and final season in the NFL. In all, Testaverde made 32 NFL starts and appeared in seven other games after the age of 40. 

While the sample size of quarterbacks playing into their 40s is very small, it has been done. Brady seems intent on eventually joining that group.

Conclusion

There's no doubting that Brady is a long-shot to play until his 45th birthday, and it may be a stretch to say he could top the 44-year-old mark that Moon, DeBerg and Testaverde all reached late in the their NFL careers. 

But it certainly isn't impossible, and if there's anybody that can pull it off, it may be Brady. According to Welker, everything in Brady's life revolves around making the quarterback a better football player.

"

In every decision he makes and everything he does—from what he eats, to what he drinks, to what his traveling schedule is—everything is centered around football. Everything … Every decision he makes is literally towards being a better football player.

"

That kind of dedication to the game will give Brady every chance to play into his 40s. The factors weighing against him—his body's health as he ages, the increased awareness of head-related injuries in the sport, the potential of losing his coach and getting replaced as a starter—could still drive him out of the game over the next handful of seasons. 

Yet given all the factors in deciding a career arc, a prediction of age 42 or 43 as the last season for Brady—meaning he still has seven or eight years left—isn't stretching reality.