Despite the skipped start, the Yankees believe that Pettitte will still be available to throw close to 100 pitches in his first scheduled start of the regular season, which would be on April 2 against the Blue Jays.
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He was also sidelined last spring after feeling back spasms in a similar location, suffered while performing squatting exercises.
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Pettitte's final Grapefruit League appearance is tentatively scheduled to come on Thursday against the Pirates at Legends Field. Girardi said that Pettitte should be able to get to 85 or 90 pitches in that start.

"I was really feeling pretty good last night, and feeling good about it, what today was going to bring," Pettitte told reporters back in Tampa. "Then I woke up this morning and it was kind of tight on me again. I’ve already lost two days. I don’t want to set it back any. I’m just going to wait until tomorrow and hopefully it’s a lot better and I can feel comfortable playing catch."