CHICAGO -- The situation was eerily familiar as Indiana held a 10-point lead over hard-charging Illinois on Friday.
But instead of the collapse and stunning loss that occurred five weeks ago, the Hoosiers held firm and they advanced to the Big Ten tournament semifinals with an 80-64 victory over the Illini at the United Center.
"We learned from that game," Indiana forward Christian Watford said. "We looked at the film last night and we looked at some things. We know we shouldn't have done some things. We let one get away."
The Hoosiers and Illini met Feb. 7, a 74-72 Illini shocker over then-No. 1 ranked Indiana.
This time, the Hoosiers led from start to finish and were only briefly threatened in the second half.
Cody Zeller collected a game-high 24 points and four teammates also scored in double figures in the conference quarterfinal opener.
The Hoosiers (27-5), who earned a first-round bye after winning the regular-season championship, advanced to Saturday's semifinals for the first time since 2006 as Watford scored 15 points, Victor Oladipo and Kevin "Yogi" Ferrell each had 12 and Will Sheehey added 11. Oladipo also had a game-high 11 rebounds.
Brandon Paul and Tracy Abrams each scored 16 points as the eighth-seeded Illini shot just 34.5 percent from the field (20 of 58). Joe Bertrand added 10 points.
Indiana meets Wisconsin or Michigan in Saturday's semifinals at the United Center.
The Hoosiers, ranked No. 3 nationally, made a case for a top seed in the upcoming NCAA tournament as they jumped to a big early lead and never trailed.
Indiana maintained double-digit leads through most of the second half and hit a high-water mark of 20 points with 53 seconds to play after a Ferrell layup.
"I'm excited about the way our guys played. They should be too," Hoosiers coach Tom Crean said. "Because they started off in a great way, they continued to play at a high level, and we closed the game the last seven minutes, not only defending pretty well, but scoring very well."
The teams were a collective 2 of 15 from the field through the first six minutes until Sheehey hit a baseline 3-pointer for an 8-2 lead. He added a shorter jumper 42 seconds later to make it 10-2.
Illinois went 6:41 between field goals before Bertrand broke the drought on a fast-break layup with 11:32 left.
Zeller reached 10 points for the game with 7:33 left in the half on a steal and fast-break layup that gave Indiana a 22-7 lead. He closed the half with 14 as Indiana opened a 35-21 lead. Paul had nine for the Illini, who shot 25.9 percent from the field (7 of 27).
Illinois' shooting improved in the second half, but the Illini weren't able to trim the deficit despite Abrams' 10 points in first 9 1/2 minutes. Illinois never cut Indiana's lead below 10 points in the span.
The Illini finally got within points eight at 60-52 on Richardson's two free throws with 8:17 showing. But the Hoosiers responded with an Olapido layup and a Watford 3-pointer to boost the lead back to double digits at 65-52 with 5:31 left.
"Had (we) not showed the resiliency and toughness that they did in the first half, we would have been down a lot more (at halftime)," Illini coach John Groce said. "I thought our defense was really good. Second half, it flipped. I thought our offense was really good and defensively we weren't able to stop them. They got too many layups, they got baskets in transition."
Zeller was 9 of 11 from the field (81.8 percent) and the Hoosiers were 27 of 50 (54.0 percent). Indiana also had a decisive 38-26 rebounding advantage.
"The key was that we had our rebounding going from the beginning and we were 26-10 at half and we were getting some putbacks." Crean said. "And where we had our lull in the second half is we weren't rebounding the way that we totally needed to. Then we got that in order and we really closed the game."
NOTES: Indiana has 21 Big Ten championships to its credit, but this was the first time in the 16-year tournament that the Hoosiers were No. 1 seed. ... Indiana finished 14-4 in Big Ten play on the way to its first outright regular-season title since 1993 and is 10-15 all time in tournament play. ... The No. 1 seed is 9-2 all time against the No. 8 seed. ... Illinois has won the most tournament games of any team with a 24-14 record and has the second-best winning percentage (.631).