As usual, Tiki Barber's retirement announcement got all the attention in North America's largest media market.

As usual, low-profile Curtis Martin flew under the radar when he declared himself done for the season _ and maybe for his career.

The status of the two marquee New York running backs illustrates one of the facts of life in the NFL: Most players have to be dragged off the field because they are hurt and/or can no longer play. Barber's announcement, in fact, got as much attention as it did because it was so unusual for a player at his peak.

More common is the attitude expressed by guard Pete Kendall, Martin's teammate with the Jets.

``If you're going to last 10, 11 or 12 years in this league, I think there is something in you that says, `I'm going to play this out as long as I can, as long as they let me,''' said Kendall, who is 33 and in his 11th season.

To understand that attitude, you have to put yourself in the strange, brutal world of NFL players.

Barber is 31, an age when most running backs are on the downslide. By that standard, his retirement announcement is no surprise.

But because he was used primarily as a punt returner and third-down back during his first five years _ 6,696 of his 9,502 yards rushing have come in the last 4{ seasons _ the NFL's current rushing leader presumably could play another couple of years, solidifying what now are marginal Hall of Fame credentials at best.

He doesn't want to do that.

Like Jim Brown and Barry Sanders before him, Barber wants to go out on top. ``I've seen backs go from 1,500 yards a season to 500 just like that,'' he said. ``I don't want to be like that.''

He also says he wants to be known as more than a football player. So the networks already lining up for his services will probably have to offer him more than just a talking-head sports job. He talks about lunching with Condoleeza Rice and interviewing Osama bin Laden's ex-mistress during his current off-season TV gig.

The subtext, however, is that football hurts.

Barber mentioned getting an e-mail after his announcement from fellow Virginia alumnus Barry Word, who had 705 carries for New Orleans, Kansas City and Arizona from 1987-94. Word's message: 12 years after he left the NFL, he still feels the pain.

That's what Martin feels.

He is 33, two years older than Barber, and his credentials are already established: 1,000 yards rushing in each of his first 10 seasons, something accomplished only by Sanders, and a total of 14,101 for his career, fourth on the career list behind Emmitt Smith, Walter Payton and Sanders.

But he also demonstrates what Barber said about players crashing quickly.

In 2004, at 31, Martin led the NFL in rushing with a career-high 1,697 yards. Last season, the injuries hit and he dropped to 735, a career low with an average of just 3.3 a carry on a 4-12 team.

But he still wanted to come back despite surgery on his knee and a continuing bone-on-bone condition (it hurts just thinking about that). Finally, last week, he conceded that his season is over and probably his career.

``I don't know if it's even possible to come back,'' Martin said. ``It hasn't been possible up to this point. I'm not looking forward to saying I'm going to definitely be back next year. It's a long stretch, I'll put it that way. That's the most honest answer I can give you.''

The fact that he still would like to come back next year is what you hear from most players at the end of their careers _ even those who don't need the money. Most veterans who have reaped the benefits of free agency either by moving or re-signing for big bucks are pretty set financially.

Mark Schlereth, for example, spent 12 years as a guard and played on Super Bowl winners in Washington and Denver. He underwent surgery 29 times _ 20 times on his knees _ and once said the only time he wasn't in pain was the 7 seconds that each play took.

Yet he hung on until 2001, when he finally realized that at age 35, there wasn't much of a market for his services.

``The truth of the matter is, after going through the 15th operation on my left knee, it became painfully obvious that I couldn't sign a six-day contract for