I would hate to be Byung-Hyun Kim:

2001 World Series, Game 4:
Tino Martinez, 9th inning game-tying homerun

2001 World Series, Game 4:
Derek Jeter, 10th inning walk-off homerun

2001 World Series, Game 5:
Scott Brosius, 9th inning game-tying homerun

2006 World Baseball Classic, Semifinal:
Kosuke Fukudome, 7th inning game-winning homerun

2006 Rockies vs Giants, 5/28/06:
Barry Bonds, Bonds passes Babe Ruth on all-time homerun list