Kansas State guard Markquis Nowell reacts after a play in...

Kansas State guard Markquis Nowell reacts after a play in the second half of an NCAA Tournament Sweet 16 game against Michigan State at Madison Square Garden on Thursday. Credit: Adam Hunger

The record-setter also was the back-breaker.

Harlem product Markquis Nowell set his hometown alight on Thursday night by establishing an NCAA Tournament record with 19 assists, scoring 20 points and taking a role in every big play during the final minute of overtime as third-seeded Kansas State took down No. 7 Michigan State, 98-93, in an NCAA East Regional semifinal before a roaring sellout crowd of 19,624 at the Garden.

Nowell fired a bullet to the rim and Keyontae Johnson went high for a behind-the-head dunk and a 94-92 lead with 52 seconds left in overtime, giving Nowell his 18th assist. After Malik Hall made one of two free throws to cut the margin to one, Nowell found Ismael Massoud for a 15-footer on the baseline for a jumper, a three-point lead and the record.

It eclipsed the mark of 18 set by UNLV’s Mark Wade in a 1987 national semifinal loss to Indiana.

Nowell then sealed the victory with a steal on the Spartans’ final possession, which he took for a layup just before the final buzzer. And all that came after what looked like a devastating ankle injury midway through the second half.

What a homecoming!

“Today was a special one, man,” Nowell said. “I’ve got to give a lot to credit to my teammates for battling, for fighting through adversity when we were down. . . . I wouldn’t have 19 assists if they didn’t make any shots.”

The Garden crowd was on its feet for the final four minutes of regulation and most of overtime as the teams waged a battle that included 14 ties and 16 lead changes.

“It was like a Rocky fight tonight,” Nowell said. “We were going back and forth, back and forth, back and forth. And some guys made some big-time plays, so I want to give credit to [coach] Tom Izzo and Michigan State.”

During a break just before his pass to Johnson for the spectacular dunk, Nowell confirmed that he’d spoken to Hall of Famer and former Knicks coach Isiah Thomas and said, “Watch this.”

Kansas State (26-9) advanced to the Elite Eight for the 13th time and first since 2018. Seeking its fifth berth in the Final Four and first since 1964, the Wildcats will meet No. 9 Florida Atlantic in the regional final.

Johnson had 22 points, Massoud, who also hails from Harlem, scored 15 and Cam Carter had 12 for the Wildcats, who shot a blistering 55.9% from the floor, including 11-for-24 on three-pointers.

A.J. Hoggard had 25 points and Joey Hauser 18 for Michigan State (21-13). Tyson Walker, a Westbury product who played at Christ the King High in Queens, had 16 points.

Walker got Michigan State to overtime after the Spartans trailed 77-70 with 4:45 left in regulation. Malik Hill’s tip-in with 52.4 seconds left got Michigan State within 82-80 and Nowell missed a three-pointer on the other end before Izzo called a timeout. The Spartans couldn’t execute the called play, but Walker scored on a drive with five seconds left to knot the score.

Nowell landed oddly with 15:31 to play and K-State ahead 50-46 and stayed on the floor, grabbing his right ankle. He had to be helped off the floor.

While he was out, Michigan State took advantage, going on a 9-2 run capped by Hoggard’s three-point play with 13:11 left for a 55-52 lead. Nowell returned right there and made perhaps his most memorable play of the game, a three-pointer before the shot clock expired that left him sprawling.

“The fall-down end-of-the- shot-clock ones?” Izzo said. “You kind of start thinking it’s not your night.”

Nowell, who wears his New York roots on his sleeve by operating under the Twitter handle @MisterNewYorkCityy and the Instagram hashtag #IRunNewYork, was gushing about the opportunity to play at the Garden on Wednesday. He made the most of it.

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