The Greyhounds (12-5, 4-1), who share the Metro Atlantic Athletic Conference lead with Iona and Niagara, trailed 47-41 with 4:47 left in regulation but tied it on baskets by Etherly and Cormier and two free throws by Robert Olson. Neither team scored in the final 2:07 of regulation.
Baskets by Jordan Latham and Cormier and three free throws by Cormier helped Loyola lead 54-49 with 1:18 left in the extra period, and Olson put it away with 4 of 4 free throws in the final 16 seconds. Loyola made 10 of 12 free throws in overtime.
Olson finished with 12 points.
Josip Mikulic scored 14 of his 16 points in the first half to help the Stags (10-7, 2-3) take a 33-27 halftime lead after trailing 13-7.
Purdue's 2016-17 prospects got a jolt Wednesday when forward Caleb Swanigan announced he will return for his sophomore season.
Clemson's Jaron Blossomgame says he is withdrawing from the NBA draft and returning to school for a final season.
Jeff Goodman logs all the coaching changes following the 2015-16 college basketball season.