During her junior year, she transferred to Marquette, where she led the team to consecutive NCAA Tournament appearances.
[2] After her college career, Collen played one year of professional basketball in Greece with BCM Alexandros.
After her tenure there, she was an assistant at Ball State, Louisville, and Arkansas, before moving to Florida Gulf Coast.
[5] Collen coached under Curt Miller with the Connecticut Sun after her time as a college assistant.
Collen led the team on an eight-game win streak including a perfect 4–0 record on the road.
[10] On May 3, 2021, Collen was hired as the head coach at Baylor following Kim Mulkey's departure to LSU.