Michigan's Duncan Robinson, left, and Moritz Wagner are pumped about...

Michigan's Duncan Robinson, left, and Moritz Wagner are pumped about Robinsons' layup with 1:10 left in the game fora 10-point lead on the way to a 75-64 victory over Michigan State in a Big Ten quarterfinal Saturday, March 3, 2018, at Madison Square Garden. Credit: Steven Ryan

The biggest shot was like the game itself — a little rough around the edges.

Muhammad-Ali Abdur-Rahkman made a critical three-pointer from long range that hit the back rim and the front rim before bouncing through the net. The shot defied description but not importance as it propelled No. 5 seed Michigan to an upset of top-seeded Michigan State, 75-64, Saturday afternoon before a sellout crowd of 19,812 in a Big Ten Tournament semifinal at Madison Square Garden.

“Rahkman crotched in that 35-footer,” Michigan State coach Tom Izzo said, offering his wry explanation of the three-ball that was like a pool shot coming off cushions with plenty of spin. It gave the Wolverines a 62-54 lead with 2:48 left. That margin was plenty sufficient given the Spartans’ struggles on offense. They shot 38.1 percent from the field.

“I think the play broke down a little and I was dribbling at the top of the key,” said Abdur-Rahkman, who scored 15 points as did teammates Moe Wagner and Zavier Simpson. “I saw the shot clock was running down and I knew I had to take the shot. It felt good. I felt like it should have swished [big grin], but it hit the back of the rim and went in.”

That’s the way the ball bounced in the second half for Michigan (27-7), the defending Big Ten Tournament champs ranked No. 15 in the nation, and which will face eighth-ranked and No. 3 seed Purdue in Sunday’s championship game. The Wolverines made 12 of 18 field goals after intermission, a sharp contrast to their 31-percent shooting in the first half, including Wagner’s 0-for-7,

“All of a sudden, a few went in for us and Moe got going,” Michigan coach John Beilein said. “This was my great motivation at halftime: I told him, ‘Hey Moe, are you going to make a shot? Because right now, you’re stinking the place up?’ He just smiled: ‘Yes, Coach, I can do that.’ ”

Wagner scored 14 points in the second half. “To be honest with you, I didn’t really care,” Wagner said of his first-half woes. “You just keep playing. When you’re confident as a team, you just let the game come to you.”

It was a rugged, ragged old-school Big Ten game, especially in the first half. Michigan State led 29-26 but neither team shot well.

“In the first half, we had some really good looks and we didn’t make them. In the second half, they got really good looks and didn’t make them,” Beilein said. “That’s what it is sometimes. Both teams played really good defense.”

Miles Bridges led the No. 2-ranked Spartans (29-4), who had won 13 in a row, with 17 points.

“We just came out really stagnant,” Bridges said of MSU’s second-half effort. “We let them get going at the three-point line and we allowed penetration.”

Bridges shot only 2-for-8 in the first half, but scored 11 points after the break to keep the game close until Muhammad-Ali’s knockout punch delighted a large contingent of Michigan fans who helped fill the Garden to capacity.

“A lot of energy in the building and we definitely fed off it,” Abdur-Rahkman said. “It felt like a home game.”