BUFFALO, N.Y. (AP) For 20 minutes, Villanova looked ordinary, vulnerable, may be even a little scared.

The Wildcats finished like champions.

Donte DiVincenzo scored 21 points and the NCAA Tournament's top seed shook off a shocking start and stumbled forward in the East region Thursday night with a 76-56 victory over No. 16 seed Mount St. Mary's.

Leading by just one at halftime, the Wildcats (32-3) opened the second half with a 21-6 run and took their first step toward defending their championship. Villanova is trying to be the first back-to-back titlist since Florida in 2007, and the Wildcats will have to play better to make history.

''I'm not annoyed,'' Villanova coach Jay Wright said. ''I really am shocked, not how Mount St. Mary's played, but that we didn't start the game with energy. We don't have time to figure it out.''

Since the NCAA went to seeding in 1985, No. 1 seeds are 130-0 against No. 16s. The historic upset remains elusive, but for a while it looked like it could happen inside KeyBank Center.

Freshman Miles Wilson scored 22 points as the Mountaineers (20-16), who edged New Orleans in a First Four matchup on Tuesday, gave the defending champions all they could handle in the first half.

''I was thinking we could get the win,'' Mount St. Mary's Elijah Long said.

But the Big East champions, who entered this tourney with more wins than any past champion, regrouped at halftime and reserved a date with Wisconsin, which beat Virginia Tech 84-74, in the second round on Saturday.

It wasn't easy. It's not supposed to be.

''They outplayed us,'' Wright said. ''At the end, we had more size and some more talented players who made plays. They deserve a lot of credit.''

Jalen Brunson scored 14 points and Mikal Bridges had 13 for the Wildcats.

Villanova not only survived a tough test from the Mountaineers but a horrendous shooting night by senior Kris Jenkins. The hero of last year's NCAA title game, when his 3-pointer at the horn defeated North Carolina, Jenkins missed his first 10 shots and finished just 2 of 13.

''I'm not worried about him at all,'' Wright said. ''

The Mount St. Mary's players wear warmups with ''Mayhem'' written on the back, and they caused quite a commotion in the early going.

Showing no fear against a team the smart-money guys in Las Vegas said would beat them by 25, the Mountaineers jumped to a 10-2 lead against the Wildcats, who missed their first eight shots, committed two turnovers and had three shots blocked in the opening 5 minutes.

''I thought we were capable of coming out and, you know, missing some shots, coming out and making some mistakes,'' Wright said. ''But the level of energy we started the game with, I just didn't think we were capable of that. I'm in a little bit of shock myself.''

Villanova's players looked nervous and played that way, and when Long threaded a no-look pass to Chris Wray for an easy basket to put the Mountaineers ahead 23-20, two seminarians - one of them clutching Rosary beads - from the tiny school in Emmitsburg, Maryland, high-fived in the stands.

Villanova, though, recovered and took its first lead at 26-25 when Eric Paschall powered home a dunk with 2:33 left in the half.

The Mountaineers left the court at halftime down only 30-29 and full of confidence.

It didn't' last.

Villanova senior Josh Hart, who sat more than 8 minutes in the first half with two fouls, opened the second half with a layup and DiVincenzo, who added 13 rebounds, hit a 3 to cap a 13-2 burst that knocked the air out of Mount St. Mary's.

Before long, the Wildcats were having their way, and except for DiVincenzo missing two breakaway dunks, Villanova showed why many believe they can win it all again.

UNDER WRAPS

Mount St. Mary's Junior Robinson, the dazzling 5-foot-5 point guard, was held to seven points on 3-of-9 shooting. He scored 23 in the First Four win at Dayton.

OFF THE MARK

Jenkins has been struggling with his shot for some time. He's 28 for 83 in his past seven games.

Wright, though, isn't concerned because while Jenkins has lost his touch, his confidence remains.

''I want him to come out firing like that,'' Wright said. ''He thinks he's going to make every shot. I love that.''

BIG PICTURE

Villanova: The Wildcats showed why they're champions by stepping up when it counted, shooting 63 percent in the second half. DiVincenzo has emerged as a major contributor of late, something Nova has needed with Jenkins struggling.

Mount St. Mary's: With all five starters coming back, the Mountaineers should be in position to get back in the NCAA field.

''Everyone got a glimpse of how good we can be,'' coach Jamion Christian said. ''It shows that when you have a program, no matter your seed, and you have guys committed to a plan and a high level of enthusiasm, that anything is possible.''

UP NEXT:

Villanova: Plays Wisconsin on Saturday for a spot in the Sweet 16.

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