Junior guard Will DeBerg had 19 points and the visiting Tommies (18-6 overall, 15-4 MIAC) avenged a January home buzzer-beater loss to Bethel with Wednesday's 69-55 win over the Royals (14-10, 10-9) in MIAC men's basketball.
Sophomore guard Erik Tengwall scored a career-high 13 points for the Toms, who secured a top-two playoff seed and first-round bye.
Taylor Hall scored 16 for BU, which made just 5-of-24 from 3-point range.
With both a Saturday win at home over St. Mary's and a Gustavus home loss to Bethel, UST would share the MIAC championship. The Tommies have already secured the program's 10th top-two MIAC finish in the last 11 seasons.
UST sank eight 3-pointers, shot 52 percent from the field, had just 10 turnovers. The Toms never trailed in the final 30 minutes and slowly extended a 28-23 halftime lead.
DeBerg canned back-to-back treys to cap a 13-3 run that built a 14-point lead at 51-37 with 10:04 to go.