CHAMPAIGN —  Chris Griffey promised his son, Tyler, that he was going to make it to Thursday’s Illinois game with top-ranked Indiana.

And it’s a good thing the elder Griffey made the drive from Wildwood, Mo.

Tyler Griffey’s layup just before the buzzer sounded gave the Fighting Illini an unbelievable 74-72 victory over the Hoosiers.

“Great win for our program,’’ Illinois first-year coach John Groce said. “I’m most happy for our players, most happy for our seniors. I thought they really stepped and made big plays.’’

And as the Orange Krush rushed the court following Griffey’s game-winner, the father stood along the baseline soaking in the experience.

“He hasn’t been able to make it up for the last couple of games because either the weather or problems with his truck,’’ Tyler said. “But, he called me today before the game and said he was definitely going to be here tonight.

“This was an unforgettable experience and I’m glad he was here to enjoy it.’’

Also standing there with Mr. Griffey were Tyler’s high school and his youth coach, Dave Sellers, who has made a few trips to Champaign recently to help Tyler with his shot.

Griffey came into Thursday’s game with a horrendous shooting slump. The senior forward was 0-for-20 from 3-point range in his previous eight games.

But after missing his first two against Indiana, Griffey finally knocked down a long-range jumper with 16 minutes left in the game.

“I just said to myself, ‘finally’,” Griffey said. “I got a lot of shots up between when I started missing to now. So much that my wrist has been hurting, I’ve been getting treatment on my wrist.’’

But on his biggest shot of the night, a wide-open layup, the only question was the clock.

Did he get it off in time?

“No doubt in my mind,’’ Griffey said. “I was actually deciding if I was going to dunk it or not.

“But in midair, I decided that I shouldn’t. I just pulled my hands back and it went in.’’

Illinois senior guard Brandon Paul, who made the pass, quickly corrected Griffey.

“He was going layup the whole time,’’ Paul said.

Even though the players and the fans were celebrating on the court, it still took Big Ten official John Higgins a few minutes of watching the replays to confirm the game-winning basket.

But, how did Griffey get that wide-open?

“We ran one of our standard out of bounds plays. I made a simple curl cut. I left two guys behind me and Brandon made a heck of pass,’’ Griffey said. “It was part of a read. I curled and didn’t expect it, but Zeller and Watford were in front of me, I went through them. They both stayed there.’’

And according to Groce, he just went with one of his normal inbound plays.

“We couldn’t draw it up, we didn’t have a timeout,’’ Groce said. “We went with one that our guys knew well.’’

And the first-year Illinois coach thought Paul, his senior guard did a great job of setting up the game-winner.

“My old college coach at Taylor University, Paul Patterson, says the best inbounder has the guts of a burglar,’’ Groce said “(Brandon) let it develop, saw the curl cut and made a great pass and a great read.’’

For Indiana coach Tom Crean, the game-winning play for Illinois (16-8 overall, 3-7 in the Big Ten) was just one of many breakdowns by his Hoosiers.

“We didn’t communicate,’’ he said. “They’re very deserving of the win, they never gave in.’’

But the Indiana coach was also disappointed that his Hoosiers (20-3, 8-2) were not able to put away the Illini when they built a 14-point lead in the first half and led 41-29 at halftime.

“We played with great toughness, great togetherness,’’ Groce said. “I would have said that regardless of how they score turned out.

“I thought we played with a lot of passion. I thought we played the game the right way today.’’

And with this victory, Illinois snaps a four-game home losing streak and it’s just the third victory over a top-ranked team in school history.

“I think it says a lot about our character,’’ said Paul, as the Illini went from 12-0, ranked 10th in the nation to the team that entered Thursday’s game with losses eight of their previous 11 games. “We have prepared for each game the same. We battled, and we fought tonight.’’

But, the biggest difference for Illinois was on the defensive end.

In their two previous losses, the Illini have sent their opponents to the free-throw line for more than 30 attempts. Indiana was just 13-of-14 at the charity stripe and the Hoosiers were guilty of 14 turnovers, leading directly to 28 points for Illinois.

“We got stops, we got rebounds and it led to offense,’’ said Griffey, who added a team-high eight rebounds to his 14 points.

Illinois senior D.J. Richardson scored a game-high 23 points, including eight during the Illini 12-2 run in the final 2:53.

Both teams are back in action on Sunday with Indiana playing at Ohio State, while Illinois plays at Minnesota.