Boston went on to participate in the first World Series held between the AL and National League (NL) champions.

The offense was led by Buck Freeman, who hit 13 home runs and had 104 RBIs, and Patsy Dougherty with a .331 batting average.

While they briefly fell into second place in mid-June, behind Philadelphia,[202] Boston then won 9-of-10 to recapture the lead, which they held through the end of the season.

The Americans met the Pittsburgh Pirates in the first modern World Series, an agreement between the AL and the NL as a post-season tournament.

The first championship of what is now 9 for the long-running club, the series would be immortalized in the 2004 remake of the team's fight song Tessie by The Dropkick Murphys, honoring the victory over the Pirates in Game 5, helped in part by that song which was adopted as an anthem by a group of team supporters, the Royal Rooters, under saloon owner Michael T. McGreevy.