But TNU scored the next four points and 12 of the final 15 of the game for a 25-16 victory.
Cumberland continued to fight throughout, but especially in game three. The teams tied five times in the first 14 points because Trevecca used an 8-1 run to take a 15-8 lead.
CU cut into the deficit but still trailed 21-16 before making a late run before a pair of kills by Simpson cut the TNU lead to three.
Two more kills from Samantha Bellar sliced the TNU advantage to one at 22-21.
Another Bellar kill and three Trojan errors gave Cumberland a slight lead at 25-24. The teams battled back and forth until TNU scored two straight for a 29-27 game three victory and the match.