No. 21 WSU men’s basketball (21-6, 12-4 Pac-12) beat No. 4 Arizona (20-5, 11-3 Pac-12), jumping into the top spot in the Pac-12 with only five games left.

The Cougs already beat Arizona once this year, shocking them in Pullman. They also beat Arizona last year. Despite what the win probability metrics and Vegas odds said, this was always a possibility.

Opening the game right was Jaylen Wells, who hit two jumpers to score five of WSU’s first seven points. Rueben Chinyelu strung together two of his own, and not long after that Wells hit another three.

The usual suspects were struggling in the first half, but the Cougs were still keeping it neck-and-neck throughout. The game was tied 24-24 with just over six minutes left in the half, but Wells and Chinuelu hit two more jumpers and Isaac Jones hit his first soon after to give the Cougs a 7-point lead.

Arizona chipped away at that lead until a Caleb Love 3-pointer gave them the lead with 47 seconds left in the half. A pair of Andrej Jakimovski free throws flipped it back, and the Cougs entered halftime up by a single point.

If anyone was the hero Thursday night, it was Jaylen Wells. At the end of the first, he had 13 points, and he was not done yet.

Arizona had no answer for Chinyelu, who scored eight points off the bench on 100% shooting in the first half. He was also leading the game in rebounding with five, two of them offensive.

Myles Rice and Jones combined for five points through the first, shooting 18.2% as a duo.

Leading a team like Arizona at the half can be a scary thing. The top offense in the country has a tendency to go on huge runs and knock their opponents out of the game in a matter of minutes, so a 1-point lead was not going to cut it.

Chinyelu opened the second half with yet another jumper. The Cougs were not struggling to score, but the Wildcats consistently responded to keep it close. With 18 minutes left in the game, Arizona took the lead again.

They held a slim lead for five minutes before a pair of assisted Jones makes, a dunk and a jumper, gave the lead back to WSU. He was fouled twice after those makes, and his resulting four free throws were all true to give him a personal 8-0 run in a span of a couple of minutes.

The lead continued to bounce between the two teams for much of the remainder of the game, with Arizona never pulling ahead by more than 1 point until Love was fouled on a layup with under a minute left. His free throw made it a 3-point play and gave the Cats a lead of the same amount.

For the first time in the second half, the Cougs were on the ropes. Arizona had finally found the big shot they were looking for, and the Cougs had a decision to make.

There are two opposing philosophies down three with 51 seconds left. You can quickly go for the easier two, hoping to get the stop and need just another two to win. Alternatively, you can go for the harder 3-pointer, tying the game.

Neither option wins you the game. Evidently, that was not good enough for Wells.

With 32 seconds left, Rice attempted and missed a 3-pointer. The game felt momentarily out of hand as everyone battled for the rebound down low. 

Jakimovski was in the midst of one of his worst shooting games of the season, but as those who watch him play know, that is not all he does. The longtime Coug emerged from the scrum with the ball, rifling it to Wells in the corner.

Wells pulled up, the ball leaving his hands just before Keshad Johnson knocked him down for the foul. The shot was perfect, giving Wells 24 on the game and tying it up.

His teammates helped him up, and the former Division II All-American went to the line with the chance to take the lead. As expected, he swished it, and the Cougs led 75-74 with 24 seconds left.

With one shot clock left, Love and the Wildcats controlled their destiny. A make of any kind would have the Cougs looking for a miracle in the closing seconds.

Teams as good as Arizona are almost never down late in the game to teams with WSU’s pedigree. Perhaps that lack of relevant experience is why, as Love drove to the basket, he slipped.

As he fell, he kicked the ball out to an open shooter, who drilled the 3-pointer. Unfortunately for the Wildcats, slipping is traveling. Love was whistled for a turnover with four seconds left, all but losing the game.

When Wells was fouled, he made sure of it. His two free throws gave him a career-high 27 points and iced the game for the Cougs.

The final score was 77-74. With the win, the Cougs move into the top spot in the conference. They swept Arizona this year and hold the tiebreaker over them, meaning if the Cougs win out they will win the Pac-12 regular season and hold the top seed in the conference tournament.

The win over No. 4 Arizona is the first over a top-5 team for WSU since 1983. Along with their previous seven wins, it marks the first eight-game in-league winning streak since 1947. 

Combined with the win over Arizona earlier in the year it makes the first sweep of Arizona since 2010 and makes this the first season ever where the Cougs have won against multiple top 10 teams.

There’s no telling where the Cougs could end up ranked on Monday. They’ve gone from on the bubble of the tournament to somewhere around a five seed, and they have four more regular season games against worse teams than Arizona to climb further up.

Their first chance to do that will come against Arizona State. That game will tip-off 5 p.m. Saturday. Fans can watch on Pac-12 Network.