Osenieks scored while being knocked to the floor and made the ensuing free throw to cap a 16-4 run that put Minnesota up 67-37 with 7:31 to play. Wally Ellenson scored on a reverse dunk two minutes later.
It was the final nonconference game for the Gophers, whose only loss was to top-ranked Duke on Nov. 22. Minnesota will begin Big Ten play at home on Dec. 31 against No. 20 Michigan State.
Based on rankings, Michigan — like Minnesota — is supposed to be a middle-of-the-pack team in the Big Ten. Michigan, Indiana, Ohio State and Illinois are all ranked in the top 10.
However, with arguably the best team in Tubby Smith's six seasons as coach, the deep and athletic Gophers are showing they could be better than pollsters believe.
The Gophers forced 19 turnovers, including 12 in the first half, mostly by keeping Lafayette to the outside and jumping into passing lanes.
Minnesota has four players averaging double figures in points. Mbakwe, who got his first start of the season, is averaging 9.2 points. The sixth-year senior had been coming off the bench as he works his way back from surgery for a torn knee ligament that ended his 2011-12 campaign in the seventh game.
Playing its first game in 11 days because of final exams, Minnesota showed early rust, but Maverick Ahanmisi and Osenieks made 3-pointers to key a 14-3 run and put the Gophers up 18-9 midway through the first half.
The starters then went on a 10-2 run, and finished the half on a 9-2 spurt, including two dunks by Coleman for a 37-22 halftime lead.
When the long-range shots didn't fall, the Gophers rebounded and scored. Minnesota finished with a 46-25 rebounding edge, and outscored the Leopards 25-2 in second-chance points, and 40-16 in the paint.
Lafayette, tied for fourth in the Patriot League preseason poll, is off until traveling to play Stanford on Dec. 28. Lafayette will begin league play on Jan. 12.