IRVINE — Both coaches came in wanting to mix things up. And, well, the rematch of the 2012 NCAA men's volleyball final between defending champion and top-ranked UC Irvine and visiting USC on Friday certainly delivered in that department.

The No. 8-ranked Trojans, who were swept in their season opener at UC San Diego on Thursday, turned the tables to stun previously unbeaten UCI, 25-21, 25-23, 27-25, in front of 1,726 at the Bren Events Center.

For the Anteaters, who won the season-opening UC Santa Barbara Invitational and improved to 4-0 by topping No. 4-ranked Pepperdine in three sets on Tuesday, it put an end to talk of an unbeaten season. UCI, a unanimous preseason No. 1 nationally after winning its third NCAA title in six seasons last spring, is 1-1 in the MPSF.

USC, which received a lift from sophomore Corona del Mar High product Joey Booth, laced a jump serve into the conventional wisdom formulated about the two programs by back-row observers.

"I don't believe that you have to fail to learn," UCI first-year coach David Kniffin said after his team posted a .183 hitting percentage, 98 points worse than the Trojans. "But there's no question that we grow from this. We should grow every time we step on the court. The one thing I think this might do for us is remind us that any team in this conference can win any night."

UCI inserted freshman Kyle Russell into the starting lineup for sophomore Zack La Cavera at opposite, after La Cavera had a match-best 16 kills and hit .577 against Pepperdine. In addition, Connor Hughes started at outside hitter, in place of fellow junior Jeremy Dejno.

USC, with Booth making his first career start (he had three career kills coming in), took a while to find its rhythm. The Trojans overcame first-set deficits of 13-10 and 16-14 to eventually pull away.

Kniffin replaced starting junior middle blocker Collin Mehring with freshman Jason Agopian to begin the second set and eventually substituted for every starter except senior All-American outside hitter Kevin Tillie and sophomore libero Michael Brinkley.

Agopian (five kills on seven swings for a .714 hitting clip), sophomore Travis Woloson (productive serving) and La Cavera (seven kills, two fewer than team leader Tillie) all added a spark. But ultimately, UCI never collectively ignited for more than sporadic scoring streaks.

The biggest UCI surge came in the final set, when the 'Eaters rallied from a 22-15 deficit to tie the game at 24-24. But USC finally closed it out on its sixth match point and silenced a suddenly raucous crowd, as sophomore middle blocker Ben Lam earned the final two points on kills.

"I don't think we really found our rhythm," Kniffin said. "As I looked at our team, I don't think we had the same poise that we've had in previous matches. We have the ability to put several different lineups on the court and be competitive … As a team, we know that we're going to need a full team effort and, unlike last year, we don't have a lot of seasoned guys that can come off the bench. So, we have to season them in the early part of the year."

USC, however, tenderized UCI's previously potent offense by winning the blocking battle (13-12 after a 4-0 edge in Game 1), benefiting from superior setting from sophomore Micah Christenson (39 assists, five blocking assists and a .565 setting percentage), strong attacking from its middle blockers, and some stellar defense, to celebrate on the Anteaters' court.

"[Christenson] is our leader, but the other guy who came in and played great was Joey Booth," USC Coach Bill Ferguson said of Peter Ueberroth's grandson, who also played at Sage Hill School. "We made the decision to start him on the bus ride here. [Previous starter] Christian Rivera tweaked his thumb [Thursday] so we needed Joey to play outside, and we figured why not? He was at home in front of his home-town fans and he came out and played a phenomenal match.

"I don't know if it was Irvine's best performance, but I'm certainly proud of our guys and they way they responded to [Thursday's loss]. We did not talk about winning or losing [Friday], we talked about character responding and what our level of effort was going to be."

Robert Feathers, a 6-foot-8 sophomore middle blocker, had a match-best 12 kills (hitting .526) and also led the winners with six block assists.

"We're a young team and we've had our troubles," Booth said. "But we worked on our side of the net. Feathers was great in the middle tonight, our setting was great, and our passing was great tonight. We had all the pieces."

And Booth was gratified to have done his share.

"I've been fighting for this spot for a while and once I saw the opportunity, I had to take advantage of it," Booth said.

Kniffin said defense was the key for the Trojans.

"Mostly, they came in and gave us great defensive volleyball," Kniffin said. "[USC] played great defense and when teams do that, hitters get frustrated and they get a little impatient. That caused us to play a little bit outside of ourselves. And when we play outside of ourselves, I think we lose a lot."

barry.faulkner@latimes.com

Twitter: @BarryFaulkner5