Trailing 44-43, Utah committed a backcourt violation on its next possession, then had to foul, and Mershon made two free throws.
The Utes trailed 42-37 with five minutes remaining, but 3-pointers by Cheyenne Wilson and Iwalani Rodrigues put them in front, and Drexel missed its next five shots, a couple from point-blank range in the final minute as Utah surged.
But it wasn't enough.
Utah took a 24-21 halftime lead and never trailed in the first 20 minutes.
Rodrigues scored five quick points and the Dragons missed six of their first seven attempts, which helped Utah control the half from the opening tip.
Plouffe scored just three points in the first half for Utah, but Wilson and Ciera Dunbar made 3-pointers off the bench, and Rodrigues stayed hot. She had nine points in the first half.
Drexel's leading scorer, Hollie Pershon, was held to just two points in the first half, thanks mostly to Rodrigues' defensive pressure and a poor shooting half (1 of 8).
The first half included just three turnovers and two fouls one by each team but obviously things changed in the second 20 minutes.