Bill was a damned good hitter. In 2004 he did two unforgettable feats. In the July game against the Yankems when Varitek and A-rod had the fight, it was Mueller who won the game with a 2 run homer. In the 4th game of the playoffs against the Yankems, Mueller drove in the tying run in the 9th against Rivera.
Btw, many feel that win in July against the Yankems turned the season around for the SOX. One could say that w/o Mueller in 2004, the SOX don't win their 1st WS in 86 years.