Mark McGwire spent part of his first day on the job as the Cardinals hitting coach issuing an apology for his past steroid use. He again said he was sorry, echoing remarks he made a few weeks ago when he admitted he used performance-enhancing drugs during his time as baseball's home run king in the 1990s. McGwire, 46, said steroids gave him the opportunity to recover from injuries and get back on the field, resulting in more at-bats but not necessarily adding to his home run count.