A three-game win streak, including a 10-3 home victory over Iowa, moved MI as high as 14 before its second loss of the season, a more respectable 7-point defeat on the road at Penn State that dropped it to No. 19.
The top two teams in the Big Ten a year ago, Michigan State and Purdue face off for the first time this season trending in the opposite direction.
The Boilermakers also held Spartans star Cassius Winston to 10 points and five assists. The state of MI comes to West Lafayette after winning 8 games in a row and is much more like the favorite who won the Big Ten they started the year with.
The Spartans didn't play a good game against the Golden Gophers on Thursday, but they still found a way to win.
Michigan State ranks first in assists per game (19.8) while Purdue ranks 124th in assists allowed per game (12.5).
It's been a hard year for Matt Painter's Purdue squad. Michigan State shot 0 of 9 from 3-point range in the first half.
Purdue scored the first five points, then extended the lead to 19-4 with a 12-0 run.
"Probably the worst beating I've taken as a coach", Michigan State head coach Tom Izzo told reporters. They were completely out of sync against Purdue's defense. Someone on the Boilermakers will need to step up for them to beat the Spartans.
Purdue: The Boilermakers' usually strong defense might have been at its best against the Spartans. The Spartans missed their first 10 3-point attempts and were just 2-of-16 in the game. If Winston has a break, second and third goal scorers Xavier Tillman and Aaron Henry will have to compete for MSU to stay in the game.
Only 2017 was worse, when MI finished the season 8-5 and unranked nationally. The Boilermakers have won five of their past six home games against top-10 foes.
© Brian Spurlock, Brian Spurlock-USA TODAY Sports Michigan State guard Cassius Winston is guarded by Purdue guard Eric Hunter Jr. during the first half on Sunday, Jan. 12, 2020, in West Lafayette, Ind.
Tyler Harris finished with 17 points for the Tigers (13-3, 2-1 American Athletic Conference), who held USF (8-9, 1-3) scoreless from the field over the final 6:37.
"Probably the worst loss I've had as a coach", MI head coach Tom Izzo told reporters. Now leading the team in ppg and apg, Winston scored only 7 points with 2 assists in MSU's toughest loss this season, a 71-66 defeat to Virginia Tech in the Maui Invitational.
The Spartans next host Wisconsin in another Big Ten bout at 7 p.m. EST Friday and Purdue travels to face Maryland at 2 p.m. Saturday.