In 1998, Mark McGwire had already moved on from the Oakland Athletics. The former Rookie of the Year had been traded to the St. Louis Cardinals the previous season, in the midst of a battle with Seattle’s Ken Griffey Jr. to be the first to break the major league record for home runs. Both fell short, but McGwire’s 58 homers topped Griffey’s 56 – one of many seasons in which he would lead the league.
McGwire and Griffey continued to battle in 1998, but it was Sammy Sosa who became McGwire’s true competitor.