CHAMPAIGN, Ill. -- At this rate, no one will want to be No. 1.

Indiana became the fifth straight top-ranked men's college basketball team to lose, falling to unranked Illinois 74-72 on a buzzer-beater by Tyler Griffey on Thursday night.

The senior forward took an inbounds pass with 0.9 seconds to play and made a wide-open layup. And, just like that, the Hoosiers -- who moved into the top spot by beating then-No. 1 Michigan just a few days ago -- went down.

Indiana coach Tom Crean, whose team has been No. 1 for a total of seven weeks this season after opening there, doesn't know why the top spot is suddenly so hard to hang on to.

"I can't answer that. I'm not sure," Crean said. "I just know that these games are 40-minute games. We played at a high level for most of the game."

The Hoosiers (20-3, 8-2 Big Ten) were in charge until the final 3½ minutes when the Illini (16-8, 3-7 Big Ten) finally put together a run to take and then retake the lead.

"I know this: When we turn the ball over, we're not very good," Crean said. "And the biggest difference tonight was 28 points off turnovers to our 16."

Hoosiers guard Jordan Hulls said flatly that the No. 1 ranking had nothing to do with Thursday's loss, even for a team that some worried might be looking past unranked, slumping Illinois to a meeting Sunday with No. 10 Ohio State.

"We just didn't execute when we needed to," he said.

If Indiana falls from No. 1 on Monday, No. 2 Florida might not be a candidate to replace the Hoosiers after the Gators' loss this week to Arkansas. That could put No. 3 Michigan back on top if they can make it to Monday without a loss.