However , he was left off the post-season roster and underwent surgery as Boston won the 2004 World Series .
Defying predictions , Williamson returned in September and finished the season with a 1.26 ERA in 28 appearances .
Williamson was left off the post-season roster and underwent surgery as Boston won the 2004 World Series .
Defying predictions , Williamson returned in September and finished the season with a 1.26 ERA in 28 appearances .