Draymond Green had 22 points, 14 rebounds and six assists to help No. 10 Michigan State beat Minnesota 68-52 Wednesday night for Tom Izzo's 400th win.
"We did some good things,'' Smith said. "We just couldn't finish the right way.''
The Gophers took an early lead, tied it once and trailed by two points midway through the first half.
Then, the Spartans went on a 16-5 run, leading to a 37-27 advantage at halftime, and were up by 13 a couple times early in the second half.
Minnesota pulled within five with just under 10 minutes left, but Michigan State outscored the Gophers 22-11 the rest of the way to win a 13th straight game at home in the series.
"We lost the toughness part of it,'' Smith said. "They just outphysicaled us in a lot of ways.''
Michigan State (17-4, 6-2 Big Ten) moved into a first-place tie in the conference with its second straight win after losing two in a row.
Smith was gracious in defeat, heaping praise on a coach he has matched up with for years, dating back to his career at Kentucky, after he reached a milestone.
"He's a class guy and his teams play extremely hard,'' Smith said. "He does things the right way and his teams always come ready to play.''
The Golden Gophers (15-6, 3-5) had won three straight, including their previous two on the road. Rodney Williams scored 15 and Ralph Sampson III had 10 points for the Gophers.
Williams wished Minnesota could match up Trevor Mbakwe with Green, but its best player was on the court for seven games before his right knee buckled in a season-ending injury.
"We missed Trevor,'' Williams said. "Draymond Green is probably the best four-man in the league. He's a lot stronger than I thought.''
Michigan State made 54 percent of its shots and held the Gophers to 38 percent and outrebounded them by seven.
"We talked about having to hit the boards and get back in transition,'' Williams said. "We knew they were No. 1 in the league in rebounds and really liked to run, but when they needed a rebound, they got it.''