Jeter's Been Playing Through Tendinitis

From Mark Feinsand:

Joe Girardi confirmed that Jeter has been battling some tendinitis in his left leg just below the knee, although the captain himself didn't acknowledge that there was any problem at all.

"I'm fine," Jeter said with a smile. "I don't even know what he's talking about."

Jeter, who returned to the lineup Tuesday night, has a history of brushing away any talk of injury, not wanting to use it as an excuse. Girardi sat Jeter on Monday night (although he used him as a pinch-hitter in the ninth), citing his 17-day stretch without a day off, but the manager said Tuesday that the recent leg issue also contributed to the decision.

"His leg has been a little sore," Girardi said. "It doesn't really hurt him or bother him except to slow him down a little bit. Not sprinting, not going after balls; it's when he decelerates. He's been dealing with it for a little bit, but we've managed it. I thought it was important that we give him a day."

I wonder how long Jeter has actually been dealing with this. It could explain why he's been struggling lately. He started the month of August hitting. .353/.411/.451 over his first 12 games of the month, but since then has hit just .196/.283/.326 in his last 12.