WEST LAFAYETTE, Ind. -- Michigan State ignored the injuries and the foul trouble Saturday.

Branden Dawson, Keith Appling and Derrick Nix refused to let the surging Spartans get slowed down by a couple of big hurdles.

Dawson scored 20 points in another trip back to his home state, while Appling and Nix each finished with 17 points to lead No. 12 Michigan State past Purdue 78-65.

"Do I have it figured out? I sure didn't yesterday when (Gary) Harris didn't practice and (Travis) Trice didn't practice," coach Tom Izzo said. "But one thing we do have is some inside-outside ability. We're not one-dimensional, like some of my teams have been. I'll figure it out when I get everyone back."

Until then, the Spartans (20-4, 9-2 Big Ten) will continue to live by the simple formula that has them back on top of the toughest conference in the nation.

They have now won three straight, nine of their last 10 overall, four of their last five road games in Big Ten play and will retain at least a share of the league lead going into Tuesday's game against No. 3 Michigan -- regardless of what happens Sunday when No. 1 Indiana visits No. 10 Ohio State.

And they're doing all this at something less than full strength.

Since Wednesday night's win over No. 18 Minnesota, most of the concern was about who would be around to face Purdue's defense. Appling left the Minnesota game after his right shoulder popped out and then back in, Adreian Payne missed part of the second half with a bloody nose, Harris (back) and Dawson (sprained right ankle) played through the pain, and Trice sat out with a head injury. Trice was the only one who didn't play Saturday.

Some worried that the players could even get caught looking ahead to their looming showdown with their biggest rival.

There were even more concerns when Izzo looked at his bench a little more than five minutes into the second half and saw Payne, Harris and Appling all sitting there with three fouls each.

But like the injuries, Michigan State never let any of it get in the way of what it came to West Lafayette to do.

"They're really banged up right now and then we're able to get Keith Appling out of the game, and we can't make anything up right there," Purdue coach Matt Painter said. "That tells you something."

Purdue (12-12, 5-6) was led by Terone Johnson with 20 points and Ronnie Johnson with 15, but couldn't avoid losing for the fourth time in five games or for the fifth straight time in the series.

While it looked nothing like the record-setting 37-point loss to Indiana in their previous home game, the stats were just as telling.

Senior shooting guard D.J. Byrd took only one shot before fouling out with 88 seconds to go and didn't score a point.

Freshman center A.J. Hammons started the game by missing his first four shots and was just 3 of 8 from the field with 13 points and eight rebounds.

The Boilermakers committed nine turnovers in the first half, 14 in the game and were just 22 of 34 from the free throw line.

The combination proved too much to overcome Saturday night.

"We turned the ball over in bad situations," Terone Johnson said. "I had three in the first half that were really unforced. That's the kind of thing that really turned this game around."

There was more to it than just errant passes, though.

After the two Indiana natives, Dawson and Harris, were greeted with a cascade of boos, they responded by making the first two baskets in a game that Michigan State only trailed once -- at 8-7.

The Spartans used first-half runs of 7-0 and 6-0 to build a 31-23 halftime lead, then turned the game when Dawson scored six points in a 12-5 run to open the second half. That gave Michigan State a 43-28 lead -- even with the fouls adding up and Harris hurting after he got bumped.

"Our team is a lot different when him (Dawson) and Adreian play with the energy that they're capable of," Appling said. "It just allows other guys to play off of them."

When Appling returned with 13:16 to go, he took the cue, scoring seven points during a 9-2 spurt that gave Michigan State a comfortable 62-45 lead with 7:19 to go, and Purdue couldn't get closer than 12 the rest of the way.

"We just stayed aggressive. Every time Purdue scored, we answered back with a bucket or a free throw or something good," Dawson said. "A lot of guys stepped up and we just kept playing together as a team."