LAS VEGAS — Back to back champs.

Behind another otherworldly performance by Deandre Ayton, the Arizona Wildcats defeated the USC Trojans 75-61 on Saturday in the Pac-12 Tournament championship game.

It is Arizona’s second straight Pac-12 Tournament championship.

“Winning this championship three times in four years means a lot,” said UA center Dusan Ristic. “I’m just so proud of this team. We showed how tough we are. ... I think these last three games, we’ve played the best basketball of our season so far.”

Ayton, who had 32 points and 14 rebounds against UCLA in the semifinals, posted 32 points and 18 rebounds against the Trojans, proving to be an unstoppable force in Las Vegas.

It was Ayton’s 23rd double-double of the season, surpassing Al Fleming for the most in Arizona single-season history.

Unsurprisingly, Ayton was named the Pac-12 Tournament’s Most Outstanding Player.

“He’s a monster. He’s a beast. He’s a special talent,” said UA guard Rawle Alkins. “Deandre is just his own generation player.”

Arizona and USC were neck-and-neck until a couple of explosive plays nearly blew the lid off T-Mobile Arena midway through the second half.

Just after USC star big man Chimezie Metu picked up his fourth foul, a cutting Alkins received a pass from Ayton in the lane, and threw down a vicious dunk over Elijah Stewart to put Arizona up 51-46 with 9:29 left.

Rawle Alkins just killed a man pic.twitter.com/t07JdkM0zn — Ryan Kelapire (@RKelapire) March 11, 2018

Ayton had a thunderous slam on UA’s next possession, then made a jumper before slamming home another dunk which put Arizona up 59-49 with 5:44 left. That was UA’s largest lead at the time.

“It was a momentum changer,” Alkins said of his dunk that began the run.

USC was able to cut its deficit to 61-55 with 4:11 left, but Arizona would exit with its third double-digit win in as many days.

“These three games we played in three days were really helpful for us,” Ristic said. “We want a few days to get ready for the NCAA Tournament. But then again we gotta use this confidence and play with the same poise, same energy against whoever we play in the (NCAA Tournament).”

Ayton overwhelmingly led Arizona in scoring and rebounds, though Ristic chipped in with 16 points and Parker Jackson-Cartwright added 10 and five assists.

Alkins finished with six points, six rebounds, and five turnovers before fouling out with 2:27 left. Allonzo Trier had nine points on six shots.

The Wildcats shot 52 percent as a team.

“They played 40 minutes of straight zone and then they played really extended far out,” Trier said. “So anytime somebody extends their zone that far out, they’re going to be so vulnerable inside. And when you have a guy like Deandre Ayton, that’s fine. You want to take away shots from me and not let me get drives, then we’re going to continue to throw it in to Dusan and Deandre and punish them.”

Arizona trailed 33-30 at half. There were seven lead changes in the first 20 minutes, and neither team led by more than four. The Wildcats were burned by turnovers, committing nine in the first half. They finished with 14.

Nick Rakocevic, who hadn’t scored in double figures since Feb. 10, had 13 points, while Jonah Mathews had 11. Both were held scoreless in the second half.

Metu battled foul trouble, and had just two points and one rebound in the first half and finished with just seven points and four rebounds.

USC shot 50 percent in the first half, crushing Arizona with screen-and-rolls, but ended up at 45 percent for the game. The Trojans shot just 41 percent in the second half.

Arizona overwhelmingly won the rebounding battle, 42-19.

“This is an example of how we should play from this point on,” Ristic said. “I think if our defense is clicking we’re going to be unbeatable.

“We’ve been talking about it the whole year. It’s not easy. We just kept practicing hard and fortunately for us we’re peaking at the right time, so we just have to keep doing the same thing on defense.”

Arizona will find out who and where it will play in the NCAA Tournament on Sunday afternoon.

So the Wildcats will enjoy their Pac-12 Tournament championship for a couple days, but they still have some unfinished business ahead of them.

“We still have one more (championship) to go,” Alkins said. “We’re happy right now. We’re excited. We have two nets that we’ve cut so far, and there’s just (two) more left.”

Follow Ryan Kelapire on Twitter at @RKelapire