Larry Walker entered the St. Louis Cardinals' game at Toronto on Monday night hitting just .249 with five homers and 23 RBIs. ``A lot of people say you know when your time is up. I had an inclination last year that my time was up. I just decided to play this year and see what happens,'' Walker said. ``It's a grind. The age and the surgeries that I've had are what's pushing me back, eight surgeries and a reconstructed knee. Father time is creeping on me, and I realize that.'' Walker said he'll retire for sure if the Cardinals win the World Series. He'll also consider moving to an American League team and becoming a designated hitter. ``I think my heart will still be there, but my body is saying, `Come on buddy,''' Walker said.