Trevor Mbakwe dunked with ferocity. Ralph Sampson III pounded on his chest after drawing a foul on a putback. Colton Iverson crashed into the lane and any defender in his path.

The 16th-ranked Gophers used bulk to beat Northwestern 81-70 Wednesday night at Williams Arena.

With Al Nolen sidelined indefinitely by a broken foot, Tubby Smith went big and started Mbakwe, Iverson and Sampson III next to Blake Hoffarber and Rodney Williams.

The lineup change resulted in the most productive outing of the year for Gophers post players.

Mbakwe recorded his 12th double-double of the season with 18 points (tying his career-high) and 14 rebounds.

Iverson scored all 15 of his points in the second half. The 6-11, 260-pound center hadn't topped double-digit scoring since a Dec. 23 victory over South Dakota State. And Sampson added 14 points.

"The big lineup was pretty impressive tonight," Smith said.

Blake Hoffarber filled in for Nolen at point guard. He scored a game-high 20 points with four assists and four turnovers for the Gophers (16-4, 5-3 Big Ten).

But their size advantage created mismatches that made his job easier.

Throughout the game, 5-10 Michael Thompson, whose 18 points led the Wildcats, ended up on the block, trying to help his teammates stop Mbakwe, Sampson and Iverson.

Northwestern (13-7, 3-6) picked up 31 fouls, most of them drawn by Gophers post players. The Gophers went 31-for-46 from the charity stripe in a game played in front of an announced sellout crowd of 14,625.

"You just gotta look in the post," Hoffarber said. "Someone's going to have a mismatch."

The Gophers outscored the Wildcats 40-18 in the paint. Their 81 points were a season-high in conference games.

Williams rocked the Barn with a two-handed dunk over Drew Crawford in the first half that handed the Gophers a 13-8 edge.

The Gophers led 25-14 after Williams passed to Sampson, who threw it to Mbakwe for a dunk. Crisp passing by the Gophers' bigs cracked Northwestern's zone throughout.

Williams led the Gophers with six assists. Mbakwe and Sampson combined for six more.

"There's really no defense for that type of passing," Smith said.

Northwestern climbed out of a 29-16 hole, however, with an 11-0 run in the final minutes of the first half. The Wildcats took a 34-33 lead into the break.

But in the second half, the Gophers went back inside, where they had found success early.

Iverson scored his team's first seven points. Mbakwe's dunk plus the foul shot gave the Gophers a 43-39 lead. A Hoffarber three-pointer stretched their lead to seven. Iverson went to the free-throw line again and knocked down both to put the Gophers up 48-39 and complete a 15-5 run to start the half.

Northwestern got within 53-50 with 11:30 to play. But an 11-3 Gophers run created another wide margin. The Wildcats never moved closer than a six-point deficit in the last seven minutes of the contest, the fourth consecutive win for the Gophers.

"We didn't have the size and strength to compete with them," Northwestern coach Bill Carmody said.