St. Thomas moved into fourth place in the final standings and secured a home playoff opening game with Saturday's 8-2 home defeat of St. Olaf, coupled with Hamline's loss to Gustavus.
Kathryn Larson celebrated Senior Day with three goals. Five of her teammates also connected for goals in UST's highest scoring output of the season.
St. Thomas (11-10-4 overall, 9-5-3 MIAC) is unbeaten in its last four games (3-0-1). It plays fifth-seed Hamline Friday at 7 p.m. on home ice to open the conference playoffs, and that winner plays Saturday afternoon at top-seed Gustavus in the semifinals.