EVANSTON, Ill. (AP) -- Andrew Smith, Butler's tallest player, used his size and finished with a big performance on Saturday night.
Smith, the Bulldogs' 6-foot-11 senior center, scored a season-high 24 points and Butler pulled away in the second half for a 74-65 win over Northwestern.
Smith had 19 points in the second half -- including nine straight -- and added 10 rebounds for the Bulldogs (7-2), who shot 48 percent en route to their fourth straight win overall and fourth straight against the Wildcats (7-3).
"Andrew was pretty forceful in going after the ball," Butler coach Brad Stevens said. "I thought he played his best game of the year. Andrew was rolling."
Like many of his teammates, Smith wasn't sharp early in the game. Butler entered the game having won its last three by an average of 23.3 points, but the Bulldogs connected on only 3 of their first 10 shots.
Despite the cold shooting and being outworked early, Butler led 34-31 at the half. Northwestern, which shot just 37.5 percent for the game, was even colder from the floor.
"At halftime we were emphasizing that we had to go to the offensive glass," Smith said. "The guards did a great job of getting me the ball and getting the ball up on the rim and the ball was just falling my way tonight."
Rotnei Clarke was 4 for 6 on 3-point attempts and finished with 13 points for Butler. Kellen Dunham added 11 points and Roosevelt Jones had 10.
Dave Sobolewski scored 21 points for Northwestern, which stayed close by converting 22 of 31 free throws. Tre Demps added 15 points -- including 13 in the second half -- and Reggie Hearn had 13.
Butler used a 10-4 run to open the second half to pull away. The Bulldogs extended their lead to 11 points midway through the second half and Northwestern was never able to close the gap to less than six.
"The start of the second half, we had a hard time scoring," Northwestern coach Bill Carmody said. "It was a very physical game and they adjusted to it better than we did.
"We were dominated (inside). That's a good lesson for our two freshman centers.
Smith pulled down seven rebounds in the second half. He finished with eight offensive and two defensive boards.
Neither team was sharp from the floor early, with both teams missing inside chances and open long-range shots. Northwestern hit just 4 of its first 11 attempts from the floor.
Sobolewski was the lone Wildcat with a consistent offensive touch in the first half, as he scored 14 points in the opening 20 minutes. Northwestern led 24-23 when Sobolewski scored a layup with 6:21 left in the half.
"The guy I'm impressed with is Sobolewski," Stevens said. "You talk about a tough kid. He lowers his shoulder and drives and there's not much you can do about it."
But then Butler's playmaking started to click and its shots started to drop. The Bulldogs used a six-point spurt to take a 29-23 lead en route to a 34-31 halftime advantage.
Butler was 5 for 10 on 3-point attempts in the first half, with Clarke going 3 for 3 from long range. Clarke, a senior transfer from Arkansas, scored in double figures for the seventh straight game.
A layup by Jones 1:39 into the second half extended Butler's lead to 41-33.
Then Smith took charge. He started his personal nine-point run with a layup at 8:34, and followed with a dunk to cap a fast break, two free throws and a three-point play.
"He's (Smith) the key for us," Clarke said. "To rebound like Andrew did and finish plays, it was all heart and determination. He lifted us all up and got us all going."
Sobolewski fouled out with 5:10 left in the physical second half.