The Bears had not played a match since losing to Montana State 3-2 at home Oct. 7. UNC play matches Thursday and Friday at Weber State and Idaho State, respectively, before returning home to host Sacramento State Oct. 26 at Bank of Colorado Arena.
"That flipped in the last three sets," Oates said. "We weren't as strong serving and passing. Credit Montana State they were serving more aggressive. It took us out of our offensive rhythm that we needed."
The loss drops UNC to 1-1 in the Big Sky Conference and 6-7 overall. UNC started 0-2 in the conference last year before finishing with a 13-3 record and repeating as regular-season champions.
The Bears defeated Eastern Washington 25-16, 25-18 and 25-19 with its best hitting percentage of the year, fewest number of attack errors and fewest service errors.