Updated

Achraf Yacoubou was lost in a swarm of Villanova fans who had rushed the court, mobbing the Wildcats in celebration of one of their biggest wins in recent history.

Yacoubou ignited the wild scene with a 3-pointer. It only made sense he was in the middle of the party.

Yacoubou hit the tiebreaking 3-pointer with 3:57 left to help Villanova upset No. 5 Louisville 73-64 on Tuesday night at the Wells Fargo Center.

The Villanova students packed behind each basket stormed the court after a victory coach Jay Wright's struggling program badly needed.

"Great win for us," Wright said.

The win came exactly eight years (Jan. 22, 2005) after unranked Villanova beat No. 2 Kansas at the Wells Fargo Center. At the time, the win was a sign Wright had the Wildcats headed back into national prominence. For now, Wright can only hope to build momentum off the gutty performance.

The Wildcats (12-7, 3-3 Big East) led by as many as 10 points in the first half and rallied late in the second to send the Cardinals to their second straight loss. Louisville (16-3, 4-2) had an 11-game winning streak end in a 70-68 loss to Syracuse on Saturday.

Ryan Arcidiacono scored 15 points, and JayVaughn Pinkston and Mouphtaou Yarou each scored 11 for Villanova.

"We know how good they are," Wright said of Louisville. "We still think that team can win a national championship."

Peyton Siva had 15 points and 13 assists for the Cardinals and Wayne Blackshear scored 17 points. The Cardinals didn't play like a team that was just the No. 1 team in the country. The Cardinals, a 71 percent free throw shooting team, was 12 of 24 from the line and shot 40 percent from the field.

"We did a lot of things wrong tonight, and they did a lot of things right," Cardinals coach Rick Pitino said. "It was really a simple answer as to why we lost. Our free throws were a turnover. Our foul shooting was despicable. Very simple tonight."

Up ahead, another road game, Saturday at Georgetown.

Wright's program has fallen from the Big East's elite following a run to the 2009 Final Four. The Wildcats were eliminated on the first weekend each of the next two tournaments and failed to qualify last season for the first time since 2004. The Wildcats needed this one.

"I just felt we broke through tonight," Arcidiacono said. "We just kept grinding, kept grinding."

Darrun Hilliard of the Wildcats picked off a pass at halfcourt and was fouled on the driving, crashing layup. He made the free throw to cut it to three. Yarou stepped back for the jumper to make it a one-point game. Pinkston tipped in the go-ahead basket for a 53-52 lead.

The Cardinals missed five straight from the free throw line (including two front ends of 1-and-1s) to keep Villanova's simmering upset hopes alive. Chane Behanan hit one to end the streak and tie the game at 53-all.

Yacoubou snapped the tie with a baseline 3 in front of Villanova's bench that sent his teammates into a frenzy. James Bell followed with another 3-pointer for a six-point lead and the upset win only 2:50 away.

Behanan fumbled the ball along the baseline and the Wildcats pounced. Arcidiacono was fouled and made two free throws for a 62-55 lead.

All that was left was for most of the crowd of 11,887 to count down the final seconds.

"This place is magical," Wright said.

The Wildcats used to routinely pack the Wells Fargo Center, home of the NBA's 76ers, for their biggest Big East games. Not even the No. 5 team in the AP poll was much of an attraction on Tuesday. Most of the upper deck was empty and the lower bowl had plenty of good seats available. When No. 3 Syracuse visits Saturday, the arena could be full of orange.

The Wildcats didn't need much of a crowd to make a run at an upset in the first 20 minutes. They hit their first four 3-pointers, beat the Cardinals on the boards, and hustled for every loose ball with the desire Wright would expect in a big game.

"I had no doubts," Arcidiacono said. "I didn't have any doubts we were going to win this game."

They built a 10-point lead that was erased by Louisville's 12-0 run. The Cardinals made the bulk of that run without Siva, who left after a hard fall around the basket. Pinkston ended a 4½-minute scoring drought with a three-point play and he scored the final basket of the half for a 30-28 lead.

The Cardinals led 52-46 with 8:25 left in the game but only scored 12 points the rest of the way.

"This one was tough for us, because we really needed this win, we needed to get our confidence level back up," Blackshear said. "Now we have to go back, and try to pull together as a team."