LAS VEGAS — Fittingly, the Mountain West Conference's pair of top 10 teams, the top two seeds, and the two programs that shared the regular-season crown, meet today for the third time to decide the MWC Tournament championship.

This showdown (5 p.m. MT, Versus) at the Thomas & Mack Center between No. 7 San Diego State (31-2) and No. 8 BYU (30-3) marks the first time two top 10 teams have played in the MWC title tilt and it's only the second time that two ranked teams have met for the crown.

On the eve of Selection Sunday, today's outcome is expected impact NCAA Tournament seeding for both teams.

On Friday, Cougar guard Jimmer Fredette scored a career-high, school-record 52 points, and became BYU's all-time leading scorer, in an 87-76 victory over New Mexico.

Later that night, Aztec guard D.J. Gay scored a basket with 4.9 seconds remaining to lead SDSU to a dramatic 74-72 win over UNLV.

The top-seeded Cougars handed the No. 2 seeded Aztecs their only two losses this season. Two weeks ago in San Diego, BYU beat SDSU, 80-67.

Now the Aztecs are looking for payback.

After beating the Runnin' Rebels on Friday, SDSU coach Steve Fisher was asked if a third matchup with BYU was a motivating factor going into the UNLV game.

"Absolutely not. We were preparing to play a terrific team, UNLV, that we had beaten twice and both games had gone down to the last 30 seconds," he said afterward. "Our thoughts, they're not on BYU right now, to be honest with you. Our kids aren't thinking about BYU, they're thinking about the 74-72 victory we got tonight. We'll have enough time, maybe enough time, 17 hours before we tip-off. We know who we'll play. Right now none of us, including me, are thinking of Jimmer or Dave Rose or any of them."

What do the Aztecs want to do differently than they did in the first two games against the Cougars?

"The first game at BYU they kind of ran us off the floor, kind of out-rebounded us," said SDSU forward Billy White. "The second game, we let them get wide-open shots. We kind of contained Jimmer, but we just left other people open."

Said Gay: "I would say try and not let them make 14 3-pointer again (as BYU did two weeks ago)."

Fredette poured in 43 points against SDSU in BYU's 71-58 victory in Provo on Jan. 26.

"He's just amazing. It's just impossible to stop him," White said of Fredette. "You only can contain him. We're going to try to go back to our game plan and see what we did wrong. Obviously we lost to them twice. We just got to see what happened in those two losses. We just got to try to contain him."

Of course, the major difference between today's matchup and the previous two meetings is the absence of suspended sophomore Brandon Davies. Is BYU a different team defensively without Davies?

"I don't know," said SDSU forward Malcolm Thomas. "We'll have to see."

The Aztecs pose plenty of challenges for the Cougars.

"San Diego State, we all know about them," Fredette said. "Very athletic. Can get rebounds, can shoot the ball. D.J. Gay is a great player, really leads that team."

"San Diego State is extremely frontline-oriented where they're gong to pound it in," said BYU coach Dave Rose. "They're going to really rebound the ball. We'll have the similar challenge of trying to defensive rebound the ball as we did tonight against a bigger, stronger, deep, athletic frontline."

What effect will playing three games in three days have on BYU and San Diego State?

"I think that adrenaline will take care of that," Gay said.

How do the Cougars prepare for this game?

"Just get therapy and rest and relax and try to get as many fluids as you can in you and eat right, get a good night's sleep," Fredette said. "Come back (Saturday) night and do it again. We're in the championship and we're excited. So I think the adrenaline will keep both teams very energized."