Herschel Walker, Brett Favre and 12 NFL Stars Who Just Couldn't Walk Away

The NFL is a gladiator sport, and some guys just can't walk away. Father Time comes calling for all of us sooner or later, and the truly gifted athletes usually can manage to keep from falling head-first into old age faster than other people.

But at some point, every athlete has to face the fact he isn't as young as he used to be and that his body just isn't going to carry him through another season at the level it used to.

Aches and pains become bigger and more debilitating, injuries come easier and take longer to heal, and the toll of being a professional football player just finally catches up and says payment is due in full.

The great athletes usually heed the call and try to bow out gracefully once it becomes apparent they've lost a step.

Other guys just ignore that voice in the back of their head telling them it's over and try and fight through it, reasoning their natural talent will get them through another year or two.

Here are a dozen NFL players who just couldn't let it go.

12. Deion Sanders

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DENVER - DECEMBER 11: Cornerback Deion Sanders of the Baltimore Ravens waits to enter the game against the Denver Broncos in the first half on December 11, 2005 at Invesco Field at Mile High in Denver, Colorado. The Broncos won 12-10. (Photo by Brian Ba

Deion Sanders retired in 2001, but waffled, almost coming back in 2002 before deciding to stay retired, then coming back for a two-year stint with the Baltimore Ravens beginning in 2004. He was 37 at the time of his comeback.

His numbers were unremarkable during that time, but he wasn't bad.

11. Junior Seau

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INDIANAPOLIS - NOVEMBER 15: Junior Seau #55 of the New England Patriots looks on warm ups before the game against the Indianapolis Colts at Lucas Oil Stadium on November 15, 2009 in Indianapolis, Indiana. (Photo by Jamie Squire/Getty Images)

As of this writing, Junior Seau still hasn't played since the 2009 season. It is unknown if Seau ever actually filed retirement papers with the league.

Seau was drafted in 1990 by the Chargers, had a great career, and then finished it off in Miami after the 2005 season. He then signed a one-day ceremonial contract to retire as a member of the San Diego Chargers.

After four days of pondering the meaning of life, Seau returned to football, playing three years with the Patriots. He did not play the 2010 season, but you never know when he might come back.

10. Franco Harris

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HONOLULU, HI - FEBRUARY 4: Class of 1990 Hall of Fame inductee, Franco Harris, attends the 1990 NFL Pro Bowl at Aloha Stadium on February 4, 1990 in Honolulu, Hawaii. The NFC won 27-21. Running back Franco Harris played for the Pittsburgh Steelers from

Franco Harris played for the Steelers from 1972-1983, and only was a few hundred yards short of breaking Jim Brown's all-time rushing yards record as the 1984 season dawned.

But Franco wanted a pay raise, and the Steelers, noting Harris definitely was showing his age, declined to give him a contract.

Eight games later as a member of the Seahawks, Harris retired, 192 yards short of the record.

9. O.J. Simpson

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LAS VEGAS - DECEMBER 5: OJ Simpson stands during sentencing at the Clark County Regional Justice Center December 5, 2008 in Las Vegas, Nevada. Simpson and co-defendant Clarence 'C.J.' Stewart were sentenced on 12 charges, including felony kidnapping, ar

After lighting things up in Buffalo throughout most of the 1970s, Buffalo traded the aging running back to the San Francisco 49ers prior to the 1978 season.

Instead of calling it a career, Simpson played two forgettable years before finally retiring and pursuing careers in acting, broadcasting and committing felonies.

He now resides at the Lovelock (Nev.) Correctional Center.

8. Ronnie Lott

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LOS ANGELES - JULY 27: Defenseman Ronnie Lott #42 of the Los Angeles Raiders gets into position during a preseason game against the San Francisco 49ers at the L.A. Coliseum on July 27, 1991 in Los Angeles, California. The Niners defeated the Raiders 24-

Ronnie Lott had a great career in San Francisco, and still was pretty good during his time with the Raiders, but age and injuries caught up with him.

He still was determined to play, though, and signed with the Jets in 1993, playing two average seasons there before trying to sign on with the Kansas City Chiefs in 1995.

He was injured during the preseason, tried to return to San Francisco, and then finally realized it was over and retired.

7. Joe Namath

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Quarterback Joe Namath of the LA Rams drops back in the pocket to turn the hand off during a game at the LA Memorial Coliseum in Los Angeles, California.

Yep, in this picture is an aging, hobbled, Joe Namath trying to give it one last go with the Rams.

The year was 1977, and Namath only lasted a few games as the starter before finishing the season on the sideline.

6. Johnny Unitas

Johnny Unitas tore the muscles in his throwing arm during the 1968 preseason, and that was the beginning of a string of injuries that brought Unitas to the San Diego Chargers for the 1973 season.

He should have just retired.

5. Jerry Rice

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KIRKLAND, WA - OCTOBER 19: Receiver Jerry Rice #80 (C) holds up his new Seattle Seahawks jersey after the Seattle Seahawks announced a trade on October 19, 2004 with the Oakland Raiders in Kirkland, Washington. The Oakland Raiders traded Rice to the Seat

Jerry Rice had 15 great years in San Francisco, but wanted more and got that in Oakland.

During the 2004 season, though, he was traded to the Seahawks, where he wore Steve Largent's number.

Other than that, there isn't a lot to be said for his time there.

4. Joe Montana

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24 DEC 1994: A PORTRAIT OF JOE MONTANA, QUARTERBACK FOR THE KANSAS CITY CHIEFS, DURING THEIR 19-9 WIN OVER THE LOS ANGELES RAIDERS AT THE LOS ANGELES COLESIUM IN LOS ANGELES, CALIFORNIA. Mandatory Credit: Mike Powell/ALLSPORT

Joe Montana spent his last few seasons in San Francisco injured, and then was traded to the Kansas City Chiefs for the 1993 season because Steve Young had claimed the starting job in San Francisco by that point.

Montana spent parts of 1993 injured as well, but played well when he was on the field. His 1994 season had a few really big highlights, including a duel with John Elway in which Montana prevailed, but the Chiefs were beaten in the Wildcard round by Dan Marino and the Dolphins, and Montana hung it up.

3. Emmitt Smith

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TEMPE, AZ - JANUARY 2: Runningback Emmitt Smith #22 of the Arizona Cardinals carries the ball against the Tampa Bay Buccaneers at Sun Devil Stadium on January 2, 2005 in Tempe, Arizona. The Cardinals defeated the Buccaneers 12-7. (Photo by Jeff Gross/Get

Emmitt Smith clearly had lost a step when Dallas let him go after the 2002 season.

But that didn't stop Smith from playing two more years for the Arizona Cardinals.

2. Herschel Walker

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21 Dec 1997: Running back Herschel Walker of the Dallas Cowboys runs down the field during a game against the New York Giants at Texas Stadium in Irving, Texas. The Giants won the game 20-7. Mandatory Credit: Stephen Dunn /Allsport

Herschel Walker clearly was on the downside of his career when he returned to the Cowboys in 1996, but that didn't stop him from trying to keep playing through the 1997 season.

While Walker was on the roster, he was barely used and finally retired after the 1997 season.

Now Walker said he'd like to make a comeback again at age 49 while promoting an upcoming MMA bout.

Stop. Just stop.

1. Brett Favre

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DETROIT, MI - JANUARY 02: Brett Favre #4 of the Minnesota Vikings talks at a post game press conference after a 13-20 loss to the Detroit Lions at Ford Field on January 2, 2011 in Detroit, Michigan. (Photo by Gregory Shamus/Getty Images)

Brett Favre was forced out of Green Bay because he was aging and the Packers had a young quarterback named Aaron Rodgers ready to go.

Favre had one okay season with the New York Jets marred by an injury not revealed until after the season, and then a great year in Minnesota in 2009.

Then Favre REALLY should have retired, but just couldn't and came back.

While he practically had to be tied to the bench to keep him off the field, he was nowhere near as effective as he used to be and his diminishing skills were evident in poor decisions resulting in turnovers.

After a mostly injury-free career, Favre finally started missing time due to injuries as well. Favre currently says he is retired.

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