McGwire's 13 homers in Round 1
July 12, 1999 | 00:09:05
7/12/99: Mark McGwire puts on a show with thirteen homers in the first round of the 1999 Home Run Derby at Fenway Park
7/12/99: Mark McGwire puts on a show with thirteen homers in the first round of the 1999 Home Run Derby at Fenway Park