Andy Pettitte wasn't willing to commit to the Yankees last winter until he knew for certain his body was ready to go through the grind of a baseball season. It appears he's testing his 40-year-old frame once again before making any decisions about 2013.

According to a source, Pettitte has already started his offseason training program, wanting "to see how his body will react" before informing the Yankees of his plans for next season.

It's been nearly six weeks since the Yankees were swept away by the Tigers, and although Pettitte initially said he would take about a month to mull his future, he has yet to come to a final decision.

The source said Pettitte is expected to make that decision "soon," though it was unclear whether that meant it would come this week. Pettitte has talked about not wanting to hold up the Yankees' offseason plans, so with the winter meetings set to open next Monday, it's possible he will end the suspense in the coming days.

Pettitte showed no sign of rust in returning to the mound last season, going 5-4 with a 2.87 ERA in 12 starts. He spent 12 weeks on the disabled list after a line drive fractured his left leg, but he returned in September and pitched well in the postseason.

The Yankees signed Hiroki Kuroda to a one-year, $15 million deal last week, adding a much-needed arm back into the rotation. While CC Sabathia, Kuroda, Phil Hughes, Ivan Nova and David Phelps would make up the rotation at the moment, the Yankees are hoping Pettitte decides to return for another season, giving them another high-end arm to slot in behind Sabathia and Kuroda.

After the playoffs, Pettitte said, "There's no doubt I still have the desire to compete," but he cited the difficulty of being away from his wife, Laura, and their four children during the long season.

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