No. 5 Illinois is fighting for a No. 1 seed in the NCAA tournament.
Michigan State is fighting a long shot just to get in.
The Spartans pulled off an upset Tuesday that could have a significant impact on the fate of both teams. Michigan State opened up a 19-point second-half and held on for an 81-72 win to stun Illinois in a win it will likely need to keep alive its NCAA tournament hopes.
Spartans hold Illinois to cold shooting night
Junior forward Aaron Henry led Michigan State with 20 points, five rebounds and six assists as four Spartans scored in double figures. The Spartans connected on 54.2 percent of their field goals while holding Illinois to 40 percent shooting from the floor and 29.4 percent from 3-point distance. Illinois also struggled from the line, hitting 19 of 34 attempts (55.9 percent).
Like many of the nation's top programs, Michigan State finds itself in unfamiliar territory this season and is at serious risk of missing the NCAA tournament for the first time since 1997, Tom Izzo's second season as head coach. Tuesday's win won't get the Spartans in. But it will go a long way in helping their chances.
Spartans have plenty of chances to play their way in
The Spartans have five regular-season games remaining before the Big Ten tournament. One of those games is Thursday at No. 4 Ohio State before they close the season with back-to-back games against third-ranked Michigan. They'll have plenty of opportunities to boost their resume in what just last week looked like a lost season.
Illinois, meanwhile, is playing for a different set of stakes. It's a lock to make the tournament, but remains in a dogfight alongside Big Ten rivals Michigan and Ohio State to join likely top seeds Baylor and and Gonzaga on the NCAA tournament bracket's top line. Tuesday's loss won't help the cause.
More from Yahoo Sports: