It was ugly — really ugly — but Michigan State got it done.

The Spartans, out to prove 2016’s 3-9 record was an aberration, strolled into Ann Arbor on Saturday night, jumped out to a 14-3 halftime lead, withstood a torrential downpour and emerged with a 14-10 victory over arch rival Michigan.

To say this game was a defensive struggle would be an understatement, but not totally indicative of how the game progressed. The seventh-ranked Wolverines opened the scoring with a field goal on their opening drive, but barely moved the ball at all for the rest of the half. Meanwhile, Brian Lewerke and the MSU offense got a nice rhythm going late in the first quarter after a fumble by Michigan.

Taking over just inside Michigan territory, the Spartans inched their way down the field and took the lead — one they would never relinquish — when Lewerke plunged forward for a 14-yard touchdown run.

After a series of punts, MSU regained possession and got the passing game going as the Wolverines keyed in on Lewerke’s running ability. Lewerke found four different receivers to get the Spartans deep into UM territory. On first and 10 from the UM 16, MSU dialed up a screen pass, using Michigan’s aggressiveness against it. As the UM front charged upfield, Lewerke dropped the ball off to running back Madre London who followed a parade of blockers 16 yards into the end zone.

That increased MSU’s lead to 14-3 with 8:07 left in the first half.

Fourteen points was all the MSU defense — thanks in part to mother nature — would need.

The threat of rain was on the horizon as the game approached, and the skies opened up in the third quarter. Like really, really opened up.

With the wet conditions came extremely sloppy football.

Michigan cut the lead to 14-10 on a Khalid Hill touchdown run midway through the third. After that, neither offense would sniff the end zone as the rain continued. Michigan’s John O’Korn threw interceptions on three straight possessions while Michigan State punted the ball on eight of its nine second half possessions. The only time MSU didn’t punt in the second half? It fumbled.

Yeah, things were really, really ugly.

Despite all of that madness, Michigan still had a chance in the final minute. The Wolverines took over at their own 20 with 34 seconds to go. With MSU playing soft defense to avoid giving up the big play, the Wolverines were able to work their way up the field.

First, O’Korn dumped one off to Karan Higdon for 15 yards and a dumb Michigan State penalty tacked on another 15 yards. All of a sudden, Michigan was at midfield, but UM wouldn’t get much further.

On the next play, O’Korn, who took hit after hit, somehow evaded the rush and found a wide open Eddie McDoom, only for the sophomore wideout to drop the ball on what would have been a gain down to the MSU 30.

An incomplete pass, a penalty and an 18-yard dump-off to Higdon followed, allowing Michigan to toss one into the end zone in a last gasp effort. That pass was knocked down and the Spartans held on, ensuring the Paul Bunyan Trophy would return to East Lansing.

The game is big for Michigan State in two ways. First, MSU had an absolutely horrendous 2016 season. The offseason that followed, full of off-the-field issues, was worse. But this young team, to the credit of Mark Dantonio and his coaching staff, has stuck together. Now MSU is off to a 4-1 start and is 2-0 to open Big Ten play.

The Spartans look like they will be a factor in the Big Ten East race.

For Michigan, coming off back-to-back third-place finishes in the East, this one should be a tough pill to swallow. The offensive struggles that have persisted all year were magnified against the stout MSU defense. O’Korn, filling in for an injured Wilton Speight, played poorly, but he didn’t get much help.

With Michigan’s loss, Penn State is the only undefeated team in the Big Ten East. PSU, which beat Northwestern 31-7 on Saturday, is heading into a bye week. After that, it hosts the Wolverines before traveling to Columbus to face Ohio State.

That stretch very well could decide the division — unless MSU keeps winning.

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Sam Cooper is a writer for the Yahoo Sports blogs. Have a tip? Email him or follow him on Twitter!

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