Ken Griffey Jr. would have retired this year if a hamstring injury had left him less than elite. The Cincinnati Reds' outfielder said Thursday that he wasn't sure he'd be able to play baseball at a high level after his major hamstring surgery in August 2004. Griffey tore his right hamstring from the bone and had it reattached with three screws -- an uncommon operation for an athlete. The 35-year-old Griffey proved he's still one of the best when he's healthy, batting .301 with 35 homers and 92 RBIs this season. His return from four years of serious injuries earned him the NL's comeback player of the year award Thursday in an online vote sponsored by baseball. The Yankees' Jason Giambi won the AL's award for his comeback from problems including an inflamed knee, a respiratory infection, an intestinal parasite and a benign pituitary tumor. ``I didn't really think about trying to prove to anybody that I could still play this game,'' Griffey said. ``It was more or less proving to myself that I could still go out and compete at a high level and help the team win."