The gray hairs congregate around his temples. They pepper Andy Pettitte’s close-cropped black hair. The ravages of time are settling in, and their reminders surround him daily. His declining velocity. His aging body. Longtime teammate Mariano Rivera’s much-celebrated final lap around the majors. And as Pettitte stood in front of his locker Sunday morning, with the Yankees Old-Timers’ Day ceremony unfolding just outside, he acknowledged this season could be his final trek through baseball. "I know how precious they are," the left-hander said of his remaining starts this season. "I think that’s why I take them so hard. I take every one of them like this could be my last. "Not only because I could be done this year. But physically, you don’t know what’s going to happen." The Yankees (41-34) begin a 20-game stretch tonight that will take them to the All-Star break, a span that manager Joe Girardi called "extremely important." And they still heavily rely on Pettitte (5-5 record this season, 4.20 ERA; 0-2 record, 5.93 ERA in his past two starts) who pitches Wednesday against the Texas Rangers. He wouldn’t want it any other way.