ROSEMONT, Ill. - The Illini are headed to the Final Four in St. Louis after executing what will go down as the best final four minutes of regulation in the program's history.

Nearby O'Hare International Airport had nothing on the noise inside Allstate Arena when Arizona's Hassan Adams missed a desperation three-pointer with two seconds left in overtime, allowing the Illini to celebrate one of the most improbable comebacks in the history of the NCAA Tournament.

No. 1-ranked and top-seeded Illinois shocked a crowd of 16,957 and a national television audience with an awe-inspiring 90-89 overtime victory over third-seeded Arizona, which led by 15 points with 4 minutes 4 seconds left in regulation on Saturday night.

Sixteen years after Illinois last played in the Final Four, the Illini will be Flyin' into St. Louis to meet Louisville (33-4) in a national semifinal game Saturday at the Edward Jones Dome. The championship game is April 4.

"It looked bad, but we kept playing and playing and were able to pull it out tonight," Illini junior Deron Williams said. "It feels great, the best feeling in the world right now, and it took all we had to get this win tonight."

Williams scored a team-high 22 points, including 14 in the final 8:50 of the game, including the 5-minute overtime. Luther Head, battling a sore hamstring, finished with 20 points, including 10 in the final 8:19.

The Illini (36-1) are one victory from the tying the NCAA record for most victories in a season, a record held by Duke (1986 and '99) and UNLV ('87). None of those teams went on to win the national title.

But after Saturday's mammoth effort, don't tell Illinois that the school's first national title is unattainable.

The Illini trailed Arizona 75-60 after Jawann McClellan hit two free throws with 4:04 left in regulation. That capped a 15-3 Wildcats run, after the Illini had trimmed their deficit to 60-57 on a Williams' 3 with 9:24 to play.

Who are you going to call down 15 points with little time left? Ghostbusters?

Well, actor Bill Murray, who starred in that movie, was sitting behind the Illini bench. But Murray looked out of control, waving and flapping his arms. So, the team went with Williams, Head and Dee Brown down the stretch.

Illinois had gone 5:32 without a basket when Williams hit his next 3 to cut the deficit to 75-63 with 3:50 left. Any sort of positive vibe, though, evaporated on the next possession when the Illini's James Augustine fouled out with 3:26 left.

The only explanation for what happened next was summed up by Brown after the game.

"It was just meant to be," Brown said.