by Alex Marvez

Some are clearly declining because of age, injuries or a combination of both. Other veterans will simply decide their bodies have had enough and decide to retire. And there will be those former stars who will try to continue playing but can't stick on a roster (a la Shaun Alexander) or find no takers (Joe Horn).

On this Thanksgiving weekend, here are 10 active players we should appreciate coming down the home stretch of the 2008 campaign.

Knee surgery is taking its toll on Deuce McAllister. (Alex Brandon / Associated Press)

1. Deuce McAllister

The New Orleans running back remains among the Saints' most popular players with fans screaming "Deuuuuce" every time he touches the football. McAllister, though, hasn't given Saints fans as much to cheer about during his eighth NFL season. Coming off reconstructive knee surgery, McAllister has lost his burst — his longest run in 86 carries is 12 yards — and plays primarily in short-yardage situations. That role isn't conducive to keeping a roster spot in 2009. McAllister will be 30 — the age many running backs begin a rapid decline — and set to earn $5.2 million.

At least McAllister had a memorable moment in what may be his final Saints home game pending a four-game suspension under the NFL's steroid policy. McAllister set the franchise's touchdown record with his 54th career score in last Monday's 51-29 rout of Green Bay.

2. Marvin Harrison

Like McAllister, the Indianapolis wide receiver isn't the same player after suffering a 2007 knee injury. Harrison is on pace for the lowest per-catch average (10.6 yards) of his 13-year NFL career. He isn't much of a threat in the deep passing game and is arguably Peyton Manning's fourth-best receiving option behind fellow wideouts Reggie Wayne and Anthony Gonzalez and tight end Dallas Clark. Harrison will be 37 entering next season and is set to earn $9 million. The Colts could try to restructure that contract, but it seems more likely Indianapolis will release Harrison this offseason if he doesn't decide to retire first.

The good news for Harrison: He doesn't have to keep playing to secure a spot in the Hall of Fame. That's already a lock after 1,087 catches for 14,422 yards and 127 touchdowns.

3. Jon Runyan

As the last active player with ties to the Houston Oilers, a chapter in NFL history will close when the Philadelphia right tackle calls it a career. That time may be drawing near. Runyan has started 188 consecutive games, which has taken a heavy physical toll (for example, a damaged ankle forces him to walk downstairs sideways). He also turned 35 on Thursday and will be an unrestricted free agent in 2009. If the sputtering Eagles (6-5-1) decide to overhaul their roster with a youth movement, one of this generation's most aggressive linemen — just ask Michael Strahan — may not be invited back.

4. Willie McGinest

After 15 seasons and three Super Bowl rings, the 36-year-old Cleveland outside linebacker already has said he will be retiring at the end of 2008. McGinest was the perfect fit at outside linebacker in Bill Belichick's 3-4 defensive scheme in New England. He was a shell of that player the past three seasons in Cleveland and has failed to record a sack in nine games so far this year.

5. Brad Johnson

The Dallas quarterback's playing days essentially ended earlier this month when he concluded a disastrous 1-2 stint replacing an injured Tony Romo. But while he's now a third-stringer, the 40-year-old Johnson has plenty to brag about from a 17-year NFL career. He won a Super Bowl ring as Tampa Bay's starter in 2002 and reached two Pro Bowls.

6. Lorenzo Neal

The Baltimore fullback, who turns 38 in December, is a physical freak for being able to play one of the NFL's hardest-hitting positions for 16 NFL seasons. The Chargers thought Neal was done when parting ways with him in the offseason. That proved a mistake. Neal is showing he has a little bit left in the tank for the Ravens (7-4), while the Chargers (4-7) have yet to find a comparable replacement to block for running back LaDainian Tomlinson.

7. Trent Green

We can only wonder what would have happened had the St. Louis quarterback not suffered the season-ending knee injury in 1999 that gave Kurt Warner the chance to lead the Rams to a Super Bowl title. Green did subsequently enjoy a stellar five-year stretch with Kansas City, but his 2008 return to St. Louis is a mess. In three games (including one start), the 38-year-old Green has thrown six interceptions and gotten sacked six times without notching a touchdown pass.

8. La'Roi Glover

Don't be surprised if the loquacious St. Louis defensive tackle pulls a Warren Sapp and retires in the offseason to pursue a broadcasting career. Glover, 34, already was slowing before suffering a knee injury that has further hindered his 2008 season. That's bad news for an undersized defensive tackle (6-foot-2, 290 pounds) who needs speed to maneuver around larger blockers. A 13-year veteran, Glover is set to become an unrestricted free agent in the offseason.

9. Donnie Edwards

As if playing on a 1-10 team wasn't painful enough, the Kansas City linebacker has battled nagging injuries since the preseason. Edwards, who had missed just one start the previous 11 seasons, turns 36 in April and is set to earn $5 million in 2009. That probably won't fly on a penny-pinching franchise deep into the rebuilding process.

10. Jeff Zgonina

Some big-bodied defensive tackles are able to play into their late 30s. What Houston's Zgonina is doing at age 38 is even more impressive. Among the NFL's smallest interior linemen at 6-foot-2 and 281 pounds, Zgonina has started twice this season and played in nine other games as a backup. Although he's a likely goner in 2009, the Texans probably wish they could transplant Zgonina's motor into the bodies of underachieving first-round picks Travis Johnson and Amobi Okoye.