All those three-pointers, the abundance of rebounds and a full 20 minutes of dominance suddenly disappeared from Michigan State’s grasp. So when LSU charged back, cutting the Spartans’ once-colossal lead to just four points, there was a question to answer: Would this be the turning point LSU desperately needed or a minor blemish in the Spartans’ run through the postseason?

A few minutes into the second half, freshman Gabe Brown began to craft Michigan State’s response. He hit a three-pointer, then LSU missed. Cassius Winston, the veteran point guard, scored, followed by another scoreless LSU possession. Then came a three-pointer from Aaron Henry and one from Kenny Goins, with a miss from their opponent sandwiched between.

With that, the Spartans had made their case in an NCAA tournament East Region semifinal Friday night at Capital One Arena. No, they would not be fazed by that LSU rally, and the Tigers’ smaller burst of hope later in the game would be surmounted as well. No. 2 seed Michigan State advanced to the Elite Eight with an 80-63 win over No. 3 seed LSU, and the Spartans did it behind career-best days from Brown and Henry, the two freshmen who had roles in that 11-0 run.

Had someone told Matt McQuaid before the game the two would combine for 35 points, the senior said he might have given a quizzical look.

“But, man,” McQuaid said, “they put in a lot of time and effort, and I feel like that was kind of a testimony to it.”

Henry led the Spartans with 20 points, adding eight rebounds, six assists and no turnovers, while his classmate Brown scored 15 points. Coach Tom Izzo said he had “zero” sense that Brown would have the night he had. Brown had scored more than five points only three times this season, and all of those performances came during the team’s nonconference slate. Henry had reached double figures only twice.

“It was one of those nights where I thought the basket was huge,” Henry said. “I’m glad that it was that way tonight.”

But those two freshmen delivered while usual standouts such as McQuaid and Goins had poor shooting nights. And in a way, that epitomized Michigan State’s season and how the program navigated trouble.

Near the end of January, the Spartans lost three straight games that sent their once-undefeated conference record spiraling in the wrong direction. But since then, Michigan State has only lost once, a one-point defeat against Indiana at the beginning of March. The win against LSU was Michigan State’s eighth straight, a stretch that included the team’s run to the Big Ten tournament title.

The Spartans lost Joshua Langford to a season-ending injury in late December. Nick Ward missed nearly a month with a hand injury. In the Sweet 16 matchup against LSU, Ward fell on that same hand in the second half and didn’t return. After the game, Ward said it was just a deep bone bruise and that he expected to play Sunday when the Spartans face top-seeded Duke, which held off Virginia Tech in the late game.

“Since the beginning of the year, we’ve just been resilient, versatile and tough,” said Xavier Tillman, who scored 12 points. “Everybody wants to be that guy” who steps up.

Against LSU, those two freshmen helped give the Spartans what they needed. And then, “Of course, Cassius is Cassius,” said Izzo, referring to his point guard, who scored 17 points with eight assists.

Led by Winston’s poise and vision, Michigan State’s offense flowed with ease. The Spartans racked up 22 assists on their 31 field goals. They shot better than 40 percent both from the field and from three, gathering plenty of open looks along the way.

Michigan State had won both of its previous tournament games by double digits, while LSU barely survived late runs from No. 14 seed Yale and No. 6 seed Maryland.

LSU seemed vulnerable during the first weekend of the NCAA tournament, winning despite hiccups and a trend of letting large leads slip away. But LSU still boasted that formidable frontcourt duo and a talented point guard in Tremont Waters, who single-handedly did what he could to give his team a chance by scoring 23 points Friday.

But Michigan State controlled the entire first half, outrebounding the Tigers 21-10. Missed shots seemed to hardly matter because on 10 of 18, Michigan State secured the offensive rebound.

“We put signs in the locker room,” Izzo said. “We put signs in the hotel rooms. We put signs in the hotel eating area — cut out, rebound; cut out, rebound; cut out, rebound.”

That dominance on the glass, along with committing just seven turnovers, proved to be the difference in the game, Izzo said.

When LSU started to surge back with a 5-0 run to close the first half and an 8-0 spurt to open the second, the Tigers found some energy. They suddenly found some of the rebounds they hadn’t been able to grab earlier in the game. But Michigan State always had an answer.

“We got a little nervous,” Ward said when asked of LSU’s rally. “They made a run, but we just had to step on their necks again and keep pushing.”

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