Andy Pettitte's aching back could force him to miss his first start of the 2008 season for the Yankees, according to the New York Post. "I was really feeling pretty good (Saturday) night and feeling good about what today was going to bring. But 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 again," Pettitte said on Sunday afternoon. "I doubt I'll pitch on Thursday; it may be pushed back to Friday." He hasn't pitched since March 17 and has thrown just eight innings for the Yanks this spring. He hopes to make his start on April 2 against the Blue Jays, but the Yankees would prefer to be cautious about the left-hander's back.