The career of Jason Jennings was not a long one, but it start off spectacularly with a Rookie of the Year in 2002 with a 16 and 8 record.  Jennings never had another winning record after that, though in 2006 he did finish 8th in 2006 for bWAR for Pitchers.  Jennings still finished his Rockies career with a winning record (58-56) and had 622 Strikeouts.