Michigan State has recent history on its side, but Jim Harbaugh’s had the better 2015 team

As fans, we carry our story lines from year to year. Coach A owns Coach B. Team C owns Team D. Running back E owns Team F. This serves us pretty well in a sport that doesn’t change a lot from year to year.

When the changes do come, however, they can happen overnight. The shift can be violent. Narratives hold 100 percent until they hold zero percent, with no screeching of brakes.

Michigan State’s trip to Michigan is a narrative game. It seems that the “Michigan State owns Michigan” story, which has served Sparty well for years now, is set to expire. Through six weeks, Michigan has been the clearly superior team on paper. But until the Wolverines actually take down the Spartans for the second time in eight years, we don’t know it will happen.

The average score of the last seven Michigan-MSU games: Spartans 28, Wolverines 14. Average wins over the last seven seasons: MSU 9.7, UM 6.6. You can forgive MSU fans for taking a “we’ll believe it when we see it” stance on all the “Michigan’s back!” articles. They’ve read those before, and it turned out those articles were wrong.

Still, in replacing Brady Hoke with favorite son Jim Harbaugh, Michigan appears to have made about the most significant coaching upgrade imaginable. And it appears the architect of Stanford’s currently elite (or very close to it) program and a Super Bowl trip in San Francisco has wasted no time turning Michigan into MICHIGAN, in all block letters, again. The offense isn’t particularly good, but it is less bad than expected -- the defense is absurdly good. You don’t lose if you don’t allow points, and Michigan hasn’t allowed a point for 15 quarters.

Michigan State still ranks ahead of Michigan in the polls. The Spartans are seventh in the AP and fourth in the Coaches. The Wolverines are 12th and 14th. But polls are ladder matches -- win and you move up, lose and move down -- and State hasn’t lost yet.

But they’ve tried. Despite playing zero teams ranked in the S&P+ top 60, the Spartans have won only one game by more than 14 points and spent two weeks flirting with losing to Purdue (24-21) or Rutgers (31-24).

From the perspective of computer rankings, the onus is all on Sparty. Even if you don’t pay heed to S&P+ in particular (Michigan ranks third, MSU 40th and UM is favored by a robust 21.3 points), the Massey rankings composite gives a significant advantage to the home team (Michigan fifth, MSU 22nd). State simply hasn’t played like the top-10 team it is supposed to be. Michigan simply hasn’t allowed points.

Here are the key matchups.

In six games -- half a season! -- Michigan has allowed nine gains of 20-plus yards and one of 30-plus. For context, Baylor’s offense is averaging 10 gains of 20-plus and six of 30-plus per game. Michigan hasn’t faced an offense like Baylor’s, but the Wolverines are swallowing up all big-play hopes.

Safety Jabrill Peppers (4.5 tackles for loss, five break-ups) and corner Jourdan Lewis (two tackles for loss, two interceptions, eight breakups) have led the way for a secondary that both makes and prevents big plays. If Michigan State is going to score enough points, it’s going to take some one-on-one wins.

Young State running backs Madre London (questionable for Saturday), LJ Scott and Gerald Holmes have showed decent explosiveness in open-field opportunities, but a good portion of the Spartans’ big plays come from the passing game. And by “the passing game,” I mean Connor Cook hitting Aaron Burbridge downfield. He is averaging 16.5 yards per catch and 10.6 yards per target. The rest of State’s wideouts: 12.6 per catch, 7.2 per target. Not bad, but not scary.

Though corners Jeremy Clark and Channing Stribling are far from chopped liver, one assumes we will see Lewis and Burbridge matched up quite a bit. And while Lewis has been impeccable, Burbridge is going to have to beat him a few times. That, or State will need to dust off DeAnthony Arnett, once a well-regarded recruit who has battled injuries and inconsistency but caught a touchdown against Rutgers last week.

Michigan brings quite a few strengths, but Harbaugh’s biggest success has come in the elimination of weaknesses, particularly on offense (where most recent weaknesses resided).

Michigan’s offensive line, a detriment for two years, still isn’t quite to where recruiting rankings would have suggested, but it is at the very least no longer a weakness.

A foursome of running backs -- De’Veon Smith, Derrick Green, Ty Isaac, Drake Johnson -- has averaged 5 yards per carry, 5.3 since the Utah game. The open-field opportunities are not legion (71st in opportunity rate), but Michigan has severely cut down on negative plays (31st in stuff rate). The Wolverines aren’t moving backwards, so even when they fail, they hand pretty good field position to the awesome defense.

Michigan State’s run defense hasn’t been as good as we’ve come to expect. The Spartans are 47th in Rushing S&P+ and 61st in opportunity rate. But they still create negative plays. Shilique Calhoun is more of a pass rusher than a run defender, but he’s decent against the ground game, and tackles Malik McDowell, Joel Heath, Lawrence Thomas and Craig Evans have combined for 12 tackles for loss.

Michigan isn’t as run-heavy as we might expect from a Harbaugh/Tim Drevno offense, but the Wolverines won’t score much if they’re allowing negative plays and putting quarterback Jake Rudock in awkward downs and distances. State’s tackles are strong enough to make Rudock awfully uncomfortable.

Michigan State is a good field position team. The Spartans’ field position margin (your average starting field position minus your opponent’s) is plus-5.2, 23rd in the country. Michigan is a great field position team: plus-8.6 yards per possession, sixth in the country.

Field position stems from a combination of offensive and defensive efficiency, turnovers and special teams. Michigan has actually been a bit unlucky in the turnovers department, recovering only four of 13 fumbles so far. That’s a pretty scary thought and a hint at how much the Wolverines have won (mostly) in efficiency and (a little) in special teams.

State has been much more reliant on turnovers. The Spartans have been a little bit lucky in terms of interceptions. They’re holding onto their chances (24 percent of their 25 passes defensed have been interceptions, which is a bit high), and opponents are dropping theirs (eight percent of 26 passes defensed have been interceptions).

Teams that win the field position margin are winning 76 percent of their games in 2015. Dial that down to a FP margin of only zero to four yards, and the win percentage is a healthy 58 percent. For whatever advantages Michigan has on paper in this game, State can negate quite a few by tilting the field in its favor by any means necessary -- good punting, forcing more three-and-outs than you suffer, or, most likely, turnovers. Luck or no, a tilted field will do Sparty favors.