EVANSTON, Ill. (AP) - Keshawn Martin returned a punt 57 yards for a touchdown just before halftime and Kirk Cousins threw two TD passes to B.J. Cunningham as No. 11 Michigan State warmed up for next week's Big Ten championship game by beating Northwestern 31-17 on Saturday.
The Spartans had already wrapped up the Legends Division title and a berth in the league championship game next week. Now they have the best record in the division, as well, and 10 victories overall (10-2, 7-1).
"We had a very challenging schedule and we felt like it was as tough as anybody's in the conference," Cousins said. "So the fact that we could win 10 and only really lose one (conference) game, to be the only Big Ten team with one loss this season says a lot about what we can accomplish here."
Cousins threw a 33-yarder to Cunningham in the third quarter and hit him again on a juggling 29-yard TD pass with 5:17 left to complete a 93-yard drive. It was the 62nd career touchdown pass for Cousins, breaking the school record held by Jeff Smoker (61).
"We talk about maturity ,we talk about focus, we talk about finishing everything that we do and this is a great example of that today," said Michigan State coach Mark Dantonio. "I think that's what we worked ford. We worked to stand alone at the top and we were able to do that today."
Northwestern (6-6, 3-5) had its four-game winning streak snapped in the regular-season finale and now hopes for a bowl bid. The Wildcats closed to 24-17 early in the final quarter on Dan Persa's 12-yard TD pass to Demetrius Fields, set up by a clutch fourth-down pass from Persa to Jeremy Ebert.
The Wildcats got the ball back at the MSU 47, but a holding penalty and Jerel Worthy's sack of Persa forced a punt and then MSU went on its long, game-clinching drive.
Martin sprinted in on his 57-yard punt return with 34 seconds left in the half as Michigan State scored two touchdowns in the final 1:40 of the second quarter and took a 17-3 lead at the intermission.
With the score tied at 3-3, Northwestern was driving when Treyvon Green fumbled after a hit by Max Bullough and Michigan State's Denzel Drone recovered at the Spartan 3 with just more than five minutes left in the half. Northwestern called a timeout - presumably to have the play reviewed - but Michigan State retained possession.
MSU then took off on a 97-yard drive - Cousins hit Brian Linthicum for 15 yards and heaved a 46-yarder to Martin that carried to the NU 7. Le'Veon Bell then carried the final 7 yards for a TD, completing an eight-play march that put the Spartans up 10-3.
The Spartans defense then forced a Northwestern punt and Martin fielded Brandon Williams' boot, broke to his right, signaled to blockers and sailed in for a 17-3 lead. The two TDs came just 66 seconds apart.
Northwestern responded quickly once the second half began.
The Wildcats' Drake Dunsmore got wide open on a blown coverage, hauled in a Persa pass and raced downfield on a 69-yard play before he knocked out at the 3. One play later, Persa flipped a 2-yard TD to Jeremy Ebert and two minutes into the third quarter, Northwestern was back in the game at 17-10.
But Cousins had a third-down keeper of 8 yards for a first down to keep the Spartans moving. And then on a third-and-13 he rolled out and avoided the rush before making a beautiful throw to Cunningham for a 33-yard TD that made it 24-10.
Cousins completed 14 of 20 for 214 yards on a drizzly overcast day and Cunningham had six catches for 120 yards. Michigan State's league-leading defense came up with six sacks. Persa completed 23 of 32 for 245 yards and two TDs.