Thomas, 22, swam 48.18 seconds on Saturday night, less than a second slower than her qualifying time of 47.37 seconds, which was a personal best.

She had come in fourth place in the preliminary race, only 0.10 seconds behind third-place University of Alabama swimmer Morgan Scott and one second behind first-place University of Virginia swimmer Gretchen Walsh.

Walsh, a freshman, came in first on Saturday night’s race, her first individual NCAA championship.

As a fifth-year senior, Thomas came into the event with the 10th fastest record, which she set at the Ivy League Championships in February.