ST. LOUIS — With its star player on the bench in a walking boot, Michigan State needed someone to pull it through another difficult game.

Sophomore Korie Lucious did — again.

Following up on his buzzer-beater in the second round, Lucious hit a whirling, fallaway jumper with 91 seconds left, lifting Michigan State back into the regional finals with a 59-52 win over hard-to-shake Northern Iowa on Friday night in the Midwest Regional.

"He stepping up for us and that's exactly what we need," Michigan State forward Draymond Green said.

Lucious' role became much bigger when Kalin Lucas ruptured his Achilles' tendon in the second round against Maryland. All the sophomore did in that game was hit the game-winning shot at the buzzer.

Against Northern Iowa, Lucious played 39 steady minutes, finishing with 10 points, six rebounds, four assists, four steals and one big shot that has the Spartans within one game of their sixth Final Four in 12 years.

"It's just from my teammates having the confidence in me to take that shot," Lucious said. "I just try to take it with confidence."

Michigan State had it relatively easy in itsMichigan State pulled it out behind Lucious, Durrell Summers' 19 points and by holding the Panthers to 10 free throws and no field goals over the final 10:21 to send the Heartland heroes home.

Always at their best in the NCAA tournament, the Spartans move on to play Sunday against sixth-seeded Tennessee, which beat No. 2 Ohio State 76-73 earlier Friday night.

"It feels great to be back," Michigan State forward Draymond Green said. "We've still got bigger dreams."

The Spartans crushed Northern Iowa's.

The Panthers (30-5) knocked off one college basketball giant but couldn't make it two straight, unable to contain the athletic Spartans for an entire game after stunning top-seeded Kansas in the second round.

Adam Koch had 13 points and Kwadzo Ahelegbe 12 for Northern Iowa, but Ali Farokhmanesh's run came to an end. The early round star was just 1 for 6 from 3-point range and finished with nine points as the Panthers' deepest run in the NCAA tournament came to a close.

"In some time, they'll have a lot to look back and a lot to be proud of," Northern Iowa coach Ben Jacobson said. "But not yet."

MIDWEST REGIONAL St. Louis No. 6 Tennessee 76, No. 2 Ohio State 73

One Evan Turner is pretty good. Five Tennessee Volunteers are even better.

Brian Williams scored the go-ahead basket on a tip-in with 32 seconds left, Bobby Maze converted a pair of late free throws and J.P. Prince blocked a desperation 3-pointer at the buzzer Friday night, leading Tennessee past Ohio State and into the NCAA tournament's round of eight for the first time.

Wayne Chism had 22 points — all but four in the second half — and 11 rebounds for the sixth-seeded Volunteers (28-8), who pulled out a back-and-forth tussle in the Midwest Regional semifinals.

They'll play No. 5 seed Michigan State Sunday for a spot in the Final Four.

Turner, a leading contender for national player of the year honors, scored 31 points — 21 in the second half. But the rest of the Buckeyes were just 3 of 16 from the field in the second half. Jon Diebler, so big for No. 2 seed Ohio State (29-8) in the first two rounds, shot 1 of 7 from 3-point range.

SOUTH REGIONAL Houston No. 3 Baylor 72, No. 10 Saint Mary's 49

LaceDarius Dunn, Tweety Carter and Baylor had all the fun, ending what had been an entertaining NCAA tournament ride for Omar Samhan and surprising Saint Mary's.

Dunn and Carter both made 3-pointers on their first shots and later combined for a highlight alley-oop dunk as Baylor rushed to a huge lead and romped in the South Regional semifinals.

No. 1 Duke 70, No. 4 Purdue 57

This is more like it for Coach K and Duke.

The top-seeded Blue Devils returned to the round of eight for the first time since 2004, with Kyle Singler and Jon Scheyer helping them pull away in the second half against No. 4 Purdue.