Neither team led by more than five points through a close first 25 minutes, as the teams traded the lead nine times and were tied seven.
Derrick Walton scored 19 points, and Zak Irvin added 18 for No. 8 seed MI (21-11), which led IL by 20 points in the first half and now meets regular-season conference champion Purdue.
The Spartans (19-13, 11-8), after losing their last two games, began this tournament by pounding Penn State Thursday 78-51.
Flying into town on the Detroit Pistons' team jet only a few hours before tipoff because Michigan's original plane slid off a runway and slammed through a fence during an aborted takeoff a day earlier, the Wolverines raced to an early double-digit lead Thursday and beat IL 75-55 to reach the Big Ten Tournament quarterfinals.
MI is now 3-2 against ranked opponents this season, including a pair of wins over Purdue, as U-M defeated the Boilermakers, 82-70, during the regular-season meeting between the two teams on February 25. The Buckeyes will get hot from 3-point range and bury the hapless Scarlet Knights, hoping that they can make a deep tourney run and push for the NCAA field (with an improbable Big Ten tourney title).
Derrick Walton Jr. led the way for the MI attack with 19 points and five assists, while Zak Irvin and Abdur Rahkman chipped in 18 and 17 apiece. He also pulled down eight rebounds and made three blocks. Power names like Indiana, Michigan State and Ohio State linger below the middle of the conference. Heck, the Wolverines even got to wear their proper blue road jerseys - with their last names printed on the back and everything - to face 13th-ranked Purdue in the Big Ten quarterfinals.
But beyond its two best players, Michigan State struggled to find much scoring. Purdue called timeout with 49 seconds left and missed a three-point attempt out of the huddle.
MI seemed to miss every three that could have extended its lead and there was turnover, missed free throw, or offensive foul waiting whenever Purdue seemed to gain momentum. He did it in Thursday's win vs. Illinois, too. Wilson leads in rebounds with 5.4 while Walton tops in assists with 4.5 and in steals with 1.1 per game.
Irvin made two layups in the extra period, with just one Swanigan free throw to counter for Purdue, giving MI a three-point lead in the final minute. A 3-pointer from the corner with 0.2 seconds left gave the Wolverines another last-second win to bolster their tournament prospects. In addition, as you may know- it is never easy to beat a team three times in a season.
The tournament starts Wednesday at 4:30 when No. 13 Penn State plays No. 12 Nebraska. The Wolverines charged from there, though, going on a 15-2 run to storm back in front.
Michigan's basketball players woke up Friday in the same city they'd be playing in that afternoon. IL dug itself a 20-point hole in the first half, rallied within eight late in the opening 20 minutes and again early in the second, and then never came closer. This was coupled with the re-emergence of D.J. Wilson for MI who scored 8 quick points to bring that MI deficit down to just one.