San Diego Chargers linebacker

Shawne Merriman

visited four different doctors to get opinions on his damaged left knee over the summer.

Specifically, Merriman wanted to know if he could play football with a torn PCL and a torn LCL.

Four doctors said he needed surgery. Merriman ignored them and declared himself available for the start of the season anyway.

"My knee still looks pretty good," he said at the time. "The decision was left up to me to play. If you give a football player a decision to play, you know, I'm going to play."

Elite athletes become elite through relentless hard work and a ton of passion for the sport they're playing. But when should someone step in and say no to an athlete who doesn't have it in them to say no themselves?

Merriman, who played one game before hanging it up and electing surgery, isn't the first example of an athlete playing through a potentially catastrophic injury. Not even close. Remember:

-Terrell Owens

, who played in Super Bowl XXXIX in 2005 despite a broken leg. Doctors wouldn't clear him to play but he did anyway, catching nine passes for 122 yards in a loss.

-Oregon quarterback

Dennis Dixon

was the Heisman Trophy favorite in 2007 before hurting his knee against Arizona State halfway through the season. He returned two weeks later against Arizona but left again when his knee buckled. It was then made public that he tried to play with a torn ACL.

-St. Louis Cardinals superstar

Albert Pujols

has played the 2008 season with a "high-grade tear" in his elbow, which is liable to blow any day. It's his call to delay surgery as long as he can. The way he can hit a baseball (even with the bad wing), nobody's going to get in his way.

 

-Even in the Beijing Olympics , China track star

Liu Xiang

tried to compete in front of his home country with a serious Achilles injury. He had barely broken out of the blocks on a false start when he finally gave up, knowing it wasn't going to work.

It seems coaches don't intervene in the professional ranks, which is up for debate. College coaches have much greater authority over their players (football coaches, in particular, take advantage of that). But in the case of Dixon, Oregon's coach allowed him to play until there was another sign of trouble.

Here's the debate: Where does it stop being the player's call and starts being someone else's? Should Chargers coach

Norv Turner

have stepped in and told Merriman no? Would the NFL Players' Association have raised a fuss if Turner didn't play Merriman? We know San Diego fans would.

 

If Merriman wanted to play through this injury while at the University of Maryland, does that change things? What about during his high school days in the Washington, D.C. area?

 

It's a gray area worth visiting. Merriman wasn't the first player to ignore a doctor's orders. You can bet he won't be the last.