Pettitte threw about 50 pitches Friday in a session that had been pushed back a day because of stiffness in his hip flexor.
"It didn’t go as well as we wanted," manager Joe Girardi told reporters in Kansas City. "He felt he could only push off 75 percent. We’ll evaluate him (here), sit him down for a couple of days.
“I definitely think he thinks it’s a setback. He just doesn’t feel like it’s completely healed."-- David Andriesen
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