ST. LOUIS — Ohio State has one of the best players in the country in Evan Turner. Tennessee has what seems like an endless supply of nasty, stingy defenders.

No secret who's going to win that battle.

Brian Williams scored the go-ahead basket on a tip-in with 32 seconds left, and J.P. Prince was relentless on Turner, blocking a desperation 3-pointer at the buzzer last night to lead Tennessee past Ohio State, 76-73, and into the NCAA tournament's round of eight for the first time.

"I was tired," Prince said. "I just said I'll save it all for defense. That's all I did. I know those last two minutes I was going to make them work. I knew nobody wanted it more than I did."

Wayne Chism finished with 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.

Tennessee will play tomorrow against Michigan State, which ended Northern Iowa's Cinderella run, 59-52

Turner, a candidate to add national honors to his Big Ten player of the year award, carried the No. 2 seed Buckeyes single-handedly in the second half. He scored 21 of his 31 points in the final period, while the rest of the Buckeyes went just 3 of 16 from the field. He actually had two shots in the final 3 seconds, but he missed from deep in the left corner, then got the ball back. With Prince all over him, Turner's last shot from near the top of the key didn't even get to the rim.

As the Tennessee players celebrated, Turner walked off the court with his head bowed.

"I can't give a percentage right now," Turner said, his eyes red and his voice catching, when asked if he'll return to Ohio State (29-8) for his senior year. "I really don't want to go out like this."

For the Buckeyes, it's an opportunity lost.

"Obviously, it hasn't hit me to the point where I think it's over," coach Thad Matta said. "They're distraught because this isn't where they thought it was going to end."

Ohio State had won four of its previous five meetings against Tennessee, including a matchup in the 2007 regional semifinals.

MICHIGAN STATE 59, NORTHERN IOWA 52

ST. LOUIS — No big shots from Ali Farokhmanesh. No mid-major magic.

Just another trip to the regional finals for Michigan State.

Durrell Summers scored 19 points and Korie Lucious hit a whirling turnaround jumper with 91 seconds left, helping the fifth-seeded Spartans survive a scare with a win over pesky Northern Iowa in the Midwest Regional semifinals last night.

Playing without injured star Kalin Lucas, Michigan State (27-8) needed a half to get used to Northern Iowa's grinding style and held 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 are one win from a sixth trip to the Final Four in 12 years.

"I knew it would be just a gut-it-out game. I'm sure everybody predicted it," Michigan State coach Tom Izzo said. "That's kind of enjoyable, to find a way. It's somewhat more rewarding than the last two."

Northern Iowa (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 the Panthers, but Farokhmanesh, the early-round star, was just 1 for 6 from 3-point range.

"We knew this was going to be a tremendous challenge and they played exactly how we thought they were going to," Northern Iowa coach Ben Jacobson said. "I'm obviously very proud of our guys."

Lucious, the replacement for Lucas who beat the buzzer with a game-winning 3 against Maryland in the second round, hit his acrobatic shot, spinning from the defense and falling away toward the top of the key. Michigan State held, then Chris Allen followed with a putback with 31 seconds left, putting the Spartans up 57-51.