Everyone in the arena knew it was upset time once Bill Murray threw up the “X” on the jumbotron.

As the final buzzer sounded Thursday night at San Jose’s SAP Center, Xavier had beaten Arizona, and Murray’s son, Luke, an assistant coach for the Musketeers, had helped pull off the biggest upset of the men’s NCAA Tournament by beating the No. 2 Wildcats.

Xavier finished the game on a 12-2 run and held Arizona scoreless in the final 2:52 to secure the win and continue their Cinderella run.

The only thing standing in between the No.11-seed Musketeers and the Final Four is the top-seeded Gonzaga Bulldogs, who defeated West Virginia 61-58 in the first game of the West regional Thursday. Xavier and Gonzaga will play at 3:09pm Saturday at SAP.

Despite an impressive defensive effort by West Virginia to limit the Gonzaga Bulldogs, who averaged 84 points per game throughout the season, the Mountaineers shot 26.7 percent from the field, hampering their ability to pull off the upset.

Gonzaga and Xavier both head into Saturday’s game with history at stake, as neither school has ever reached the Final Four. For Gonzaga senior guard Jordan Mathews, there would be no better way to finish his college career.

“Just being able to play for a Final Four is something you grow up watching,” he said. “You grow up watching March Madness and Sweet 16 games, and to have that opportunity, to be 40 minutes away with this group, with this university, is very special.”

Prior to the games, the streets of downtown San Jose flooded—not from water, this time—with alumni who traveled from all over to see their alma mater compete in the “Big Dance.”

Bay area native and West Virginia alum Matty Staudt was soaking in the scene at downtown’s Britannia Arms, where a sea of blue and gold convened before and after the game. The Mountaineers alumni association held their official pregame party at the Brit, giving Staudt some college deja vu.

“It’s surreal to be from here and see a bar full of WVU people,” he said. “It is so weird—I can’t even begin to tell you how weird it is.”

Although Staudt’s alumni reunion ended in a loss, Gonzaga and Xavier fans are expected to pour into San Jose’s over the next day with hopes of watching their team move on. More fans are expected to fill the arena than the 16,884 in attendance Thursday.

Xavier’s road to the Elite 8 has been filled with upsets, but they’ll need to find a way to put a dent in Gonzaga’s tough perimeter defense. They’ll also need to keep 300-pound, red-bearded giant Prezemek Karnowski off the boards.

The winner of Saturday’s matchup will travel on to Phoenix to face the winner of the East regional. Games for that side of the bracket are scheduled for today at Madison Square Garden. The first game will feature South Carolina and Baylor at 4:29pm, followed by Florida-Wisconsin. Both games will be televised on TBS.