Roger Clemens is prepared for his 2006 major league debut on Thursday night against the Twins just 23 days and three minor league starts after rejoining the Astros. But the 43-year-old seven-time Cy Young winner doesn't think the return would have been possible if not for one little reason, his son Koby's injured pinky finger. Playing in the WBC, followed by Koby returning home after the injury, forced him into more training during his off time than he would have done otherwise. "I don't know if I'd be here today," he said. "I don't know if I would have made that commitment because I advanced a little bit farther. It was somewhat of my spring training." His start comes exactly eight months after his last major league appearance, when he left Game 1 of the World Series with a strained hamstring.