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Not surprising, it was Tom Izzo and Michigan State that proved the only certainty on a chaotic opening day.

Two overtimes. Two upsets. And one crazy day in Spokane.

"It's the tournament so everybody is going to bring their best punch," San Diego State's Dwayne Polle said.

Michigan State, the No. 4 seed in the East Region, provided the only blowout in the second-round with a 93-78 win over Delaware behind the career-best 41 points from Adreian Payne.

Surrounding the Spartans was chaos.

It started early with Harvard becoming the latest No. 12 seed to knock off a 5 seed with a 61-57 takedown of Cincinnati. The night session saw Oklahoma taken to overtime on a late 3-pointer, then dispatched in the extra session by 12th-seeded North Dakota State 80-75.

And what appeared to be a blowout in the making at halftime became far more uncomfortable than fourth-seeded San Diego State wanted. The Aztecs were pushed to overtime on a late 3-pointer by New Mexico State's Kevin Aronis. San Diego state held on in overtime for a 73-69 win over the 13th-seeded Aggies.

"There's so many good teams in the tournament, obviously not a lot of difference," Oklahoma coach Lon Kruger said after the Sooners were bounced. "The depth and the quality of the depth is I think as good as it's ever been."

Michigan State? They just did what every pundit in America expected them to do on their way to what many expect will be another Final Four appearance for Izzo. Led by Payne's record performance, the Spartans overpowered the Blue Hens, adding credence to the idea that Michigan State was under-seeded from the start.

Delaware coach Monte Ross certainly felt that way after watching Payne put together one of the best tournament performances in the past 15 years.

"The shame of it was, in the whole spectrum of this whole thing, I thought that there were just two teams I just didn't want to play because I just thought that they were playing at a high level and coaches were tournament tested and you weren't going to sneak up on them or anything like that," Ross said. "Michigan State was one of them."

Payne's performance was the first 40-point effort in the NCAA tournament since Stephen Curry did it for Davidson in a win over Gonzaga in 2008. Payne set a school tournament scoring record, surpassing the 34 points Greg Kelser scored during Michigan State's 1979 title run led by Magic Johnson.

Payne's overall line: 10 for 15 from the field, 4 for 5 from 3-point range, and a tournament-record 17 for 17 from the free throw line. He chipped in eight rebounds, too.

"We are here to win the weekend and that's the main goal," Payne said.

Somehow Payne's performance became a footnote to the other craziness that took place inside the Spokane Arena.

A year after picking up its first NCAA tourney win by shocking New Mexico as a No. 14 seed, Harvard was back continuing its NCAA education. Siyani Chambers scored 11 points, including five straight in the final 2 minutes. Wesley Saunders led the Crimson (27-4) with 12 points as Harvard proved last year's upset was no fluke. The Crimson became the first Ivy League school with NCAA tournament wins in consecutive years since Princeton in 1983-84.

Harvard never trailed after the opening moments. Now Harvard takes on the Spartans with a chance to break every bracket.

"We all talked about just living up to our values and our standards and doing the things that have gotten us to this point," Saunders said.

The drama belonged to North Dakota State, which had Oklahoma playing catch up for most of the night, only to see the Sooners surge in front in the closing minutes.

Down 66-63, Lawrence Alexander rattled in a 3 with 11 seconds left in regulation. The Bison then survived three Oklahoma shot attempts to force the extra session.

In overtime, Alexander came through with clutch shots again, although the biggest contribution came from freshman Carlin Dupree. Having played a total of 29 minutes in the previous five games, Dupree entered after Taylor Braun fouled out. All Dupree contributed was two free throws — from a 58 percent free throw shooter — and a tough baseline basket with 41 seconds left when running time off the clock was probably the more prudent move.

But the play fit the fearless style of the Bison, picking up their first NCAA victory in their second tourney trip.

"It was a big shot, obviously, for the team," Dupree said. "I didn't want this to end for these guys, so I see how hard we worked and we stayed together as a team and I'm excited that we pulled it off."

Not to be outdone, New Mexico State nearly added a final punctuation to the night, forcing overtime against San Diego State on a 3-pointer from Aronis in the closing seconds of regulation. But the Aztecs got enough out of Xavier Thames in overtime to avoid a third upset in the building.

"The talent is pretty good everywhere," San Diego State coach Steve Fisher said.