MILWAUKEE -- Two years ago, Cincinnati brought Purdue's season to an abrupt end with a one-point victory. Last year, Arkansas-Little Rock forced a pair of overtimes before stunning the Boilermakers with a one-possession upset.

But Purdue washed the bitter taste of those first-round upsets away Thursday, using its size inside and 21 points from junior Vincent Edwards to hold off No. 13 Vermont for an 80-70 victory in a first-round Midwest Regional contest at the Bradley Center.

"Going out (in the first round the last) two years, was terrible," Edwards said. "To get this and get that monkey off your back, it feels great."

Senior forward Caleb Swanigan anchored the Boilermakers (26-7) inside, hitting five of 11 shots for 16 points while grabbing 14 rebounds for his 27th double-double of the season -- the most among all Division I players this year.

He showed his versatility, too, stepping out for a clutch 3-pointer in the second half as the Boilermakers finally pulled away from a Catamounts (29-6) squad that had led by as many as eight early in the game and trailed by just a point to start the second half.

Purdue advances to face the fifth-seeded Iowa State on Saturday. The Cyclones beat 12th-seeded Nevada 84-73.

Anthony Lamb powered Vermont early, scoring 14 of his 20 over the first 20 minutes of play. Lamb sank three of the Catamounts' six first-half 3-pointers and was 5-for-8 overall. Vermont shot just 38 percent in the first half but heated up after the break and connected on 14 of 27 shots (52 percent) but couldn't contain Edwards, who scored 15 in the second on 7-of-9 shooting.

"He had a huge second half for us," junior guard P.J. Thompson said. "Actually, it was special; he had a special second half. In the first half, he was struggling a little bit. He was down on himself, but we told him he's been doing this since he was a little kid. He steps up in big moments."

Vermont suffered a big loss late in the first half when Kurt Steidl, the team's lone senior and playing in his first NCAA Tournament contest, suffered a knee injury and left the game. Without him, the Catamounts were without a leading defender and the Boilermakers opened the second half on an 8-2 run to make it 45-38. Bell-Hanes drained a 3-pointer to cut the deficit back to four and Ernie Duncan made it 51-50 with 12:24 to play.

Swanigan drained a 3 on the other end that restored the four-point Purdue advantage. After trading baskets, Edwards hit a 3-pointer to put the Boilermakers back up seven.

"The difference in the second half, I think right off the bat, Edwards was really aggressive, got to his right hand and was making plays," Bell-Haynes said. "And I think not having Kurt in the second half to guard him, we had to put slower guys on him at certain times and really helped him out."

Vermont shot 52 percent from the field in the second half and kept hanging close, but the Catamounts just couldn't close the gap.

"Vermont is a really good basketball team," Purdue coach Matt Painter said. "Our guys did show some maturity down the stretch and making plays and getting stops and Swanigan made some huge blocks there at the end."

Thompson's 3-pointer from the top of the key with 2:08 to play made it an 11-point game, all but sealing it for the Boilermakers.

"We're obviously disappointed with the loss tonight, but I couldn't be more proud of this team," Vermont coach John Becker said. "The way they battled tonight, you know, and just gave everything they had against a really good Purdue team. I feel awful for Kurt Steidl, our senior, one of our senior leaders who is our best two-way player and a really important piece to our team."

NOTES: Caleb Swanigan finished with 16 points and 13 rebounds, good for his 27th double-double of the season -- the most this year by a Division I player and the most by any player in a season in Big Ten history. ... Vermont brought the nation's longest winning streak into the game. The Catamounts had won 21 in a row before their loss Thursday. ... Purdue is 20-7 all time in first-round tournament games, including a 15-2 mark since 1994. ... Vermont, making its sixth appearance, fell to 2-6 in NCAA Tournament games.