MLB Trade Deadline: Top 25 midseason deals of all-time

19. Cardinals acquire Mark McGwire, July 31, 1997

Their legacies have changed dramatically over the last two decades, but the historic home run chase between Mark McGwire and Sammy Sosa during the summer of 1998 was largely credited with saving baseball at a time when it desperately needed it.

Just four seasons after a strike cancelled the World Series and turned millions of fans off the sport, McGwire and Sosa hitting 70 and 66 home runs, respectively, both passing the longstanding single-season record Roger Maris set with 61 in 1961, brought legions back to the game. And McGwire’s record-setting season came the year after his trade from Oakland to St. Louis.

In 12 years with the A’s, McGwire launched 363 home runs. He won the 1987 AL Rookie of the Year Award after leading the majors with 49 homers, and made the first of nine AL All-Star teams. McGwire led the league in long balls again when he hit 52 in 1996, and finished the 1997 season with 58 homers after amassing 24 in just 51 games with the Cardinals.

McGwire spent parts of five seasons in St. Louis, and hit 220 home runs in Cardinals uniform. He followed his record season with 65 homers in 1999, the fourth time he led the majors in the category. McGwire finished his career with 583 home runs, which ranks No. 11 on the all-time big league leaderboard.

As an aside, it’s also worth noting that Sosa was a trade deadline acquisition of the Chicago White Sox in 1989, who sent him to the crosstown Cubs three years later.