Why did Denny Hamlin keep driving on a bad knee in Phoenix?

For Ryan Newman, and to a lesser extent Kyle Busch and Jeff Gordon, the Phoenix weekend was a positive, a good run that propels them forward, both in the season and in the standings.

But then, none of those guys just had knee surgery. The one driver who did, Denny Hamlin, had a much different take on Phoenix: "A miserable experience."

Hamlin, who had his knee drained before the race and was in "more [pain] than I can tell you," had an awful day all the way around. He ran as high as 13th, but problems swapping out a battery on lap 136 put him two laps down on the field.

So why not swap out for replacement driver Casey Mears, who was standing by and ready to jump in on a moment's notice? Well, plenty of reasons, all of which had to do with having a hard head, not just a busted knee.

Perhaps Hamlin was flashing back to last fall in Texas, when Jimmie Johnson hit the wall during early laps and then stayed in the car while his team worked it back into racing shape. Johnson was universally praised for his dedication to — and high expectations of — his team, and perhaps that kind of all-for-one motivation was in Hamlin's mind.

"The only thing I was going to gain was maybe some respect of the team guys just because I knew our day was shot," Hamlin said. "I wasn't going to give up on them. I wasn't going to lay down on them."

Yeah, but is that really an issue? Shouldn't he already have the respect of his team by now? The fact that Hamlin won two weeks ago in Martinsville indicates that he's got the talent to run at the top of the field even when he's not at full strength. It's obviously too early to tell whether this weekend will have any long-term effects. But if Hamlin's going to make a run at the Cup this year — and remember, should he make the Chase, he'd be in line for bonus points already — he's going to have to think longer term. Giving up a few meaningless laps in Phoenix could be worth running strong for the last few at Homestead.