Youk out, but for how long?

As expected, Kevin Youkilis is not in the Yankees lineup tonight, having undergone an MRI on his troublesome lower back earlier in the day. But as of the time the clubhouse was cleared of media before the game, the Yankees still had not received the results of the test and, according to Joe Girardi, were waiting for the doctor to arrive at Yankee Stadium before giving any estimate of how long Youkilis will be out.

Including tonight's game with the Astros, Youkilis has missed seven of the past eight games after leaving a game with the Blue Jays after five innings on April 20. But Girardi said the Yankees did not regret not placing Youkils on the disabled list last week, which would have made him eligible to come off in another week if his back responds to treatment. Youkilis played on Saturday but suffered a recurrence of the stiffness and soreness that drove him out of last Saturday's game, which means the Yankees now can only backdate his DL stint to April 27, ensuring he would be out until at least May 11.

"The player told us he was ready to go and we put him in," Girardi said of using Youkilis on Saturday. "How did it happen, I can't tell you how he re-injured it. Could it have just been from normal use or a play, that could happen anytime. I have no second thoughts."

All along, Youkilis has told the media that he was OK, and made it seem that the Yankees were being overly cautious with an injury he could play through. But today he acknowledged, "Sometimes OK is not really that great. You got to suck it up sometimes. You gotta play through things. I thought I could play through it. I just didn’t feel right after that, so I didn’t play the next day."

Youkilis is hitting .266 with two home runs and 17 RBI, having played in 17 of the Yankees 24 games so far.