Breaking down Michigan’s zone defense

Michigan’s zone defense has gone from an occasional wrinkle to a staple over the first month of the Big Ten season. Today we take a closer look at Michigan’s 2-3 and 1-3-1 zones and how effective they have been for the Wolverines this season.

Michigan’s zone defense has gone from an occasional wrinkle to a staple over the first month of the Big Ten season.

The 1-3-1 zone spearheaded several late conference victories, helping Michigan come back from 13 down against Illinois, 9 back against Minnesota and 5 points against Northwestern. A week ago at Rutgers, the Wolverines went to the 2-3 zone and were able to come back from a six point deficit in the second half. Against Wisconsin on Saturday evening, the Wolverines went to the zone again and managed to take Wisconsin to overtime.

The Wolverines utilized a zone offense on just 14 defensive possessions in the non-conference season, sticking with man-to-man defense for their other 718 half court possessions. Michigan wasn’t a great defensive team in non-conference play, but it was certainly a man-to-man defensive team.

That all changed in Big Ten play. The decision to make the switch is certainly due to some desperation, both from original defensive liabilities and now the reality of playing without Caris LeVert. The Wolverines aren’t the quickest team, they play two 6-foot guards and they have the worst post-up defense in the Big Ten. Despite all of those flaws, Michigan is ranked third in the Big Ten in points allowed per possession and sit at 5-3 overall.

After running man-to-man for 99% of its half court offensive possessions in non-conference play, the Wolverines now feature a 2 to 1 split between man and zone – and the zone is working.


Note: These point per possession numbers look low because they only include half court defense. Michigan has also surrendered 85 points on 89 transition possessions in league play. Synergy Sports calculates points per possession slightly differently than we do on a game-by-game basis as an offensive rebound counts as a new possession.

Examining the game-by-game results of the zone defense we can see that Michigan is playing more zone and playing it better as the season wears on. The following chart shows the number of half court possessions Michigan played a zone defense, per Synergy Sports, and the ratio of scores vs. stops.


Lumping all of Michigan’s zone possessions into one bucket isn’t accurate. The Wolverines have utilized two very different zone defenses this season. One is John Beilein’s famous 1-3-1 zone, the other is a fairly standard 2-3 zone with a couple of wrinkles.

With Caris LeVert in the rotation, the 1-3-1 was Michigan’s zone of choice. In the first two games without LeVert, the 2-3 zone has been the zone of choice and it has been more of a base defense than an extra option.

Beilein says the decision of which zone to play is based more on matchups than anything else.

“It depends on the game,” Beilein explained. “The 1-3-1 had been really good to us for a whole bunch of games in a row, two or three games in a row. And then we went to Rutgers and the 2 zone was really good. We’d like to think all of them are evolving so people are getting better, but then people throw new wrinkles and you have to adjust.”

“By the end of the year, hopefully they know a lot of things that they see no matter what defense we choose to play. I don’t think one is better than the other. It depends on the opponent, really.”

So which zone works best and when? Here’s a brief overview of both defenses.

2-3 zone

Michigan’s 2-3 zone is fairly standard, but the Wolverines have done a nice job in several elements recently. Michigan’s guards lack size at the top, but have been very active. That includes simple things like having the guard opposite of the ball sink in to deny the pass to the opposing player in the high-post. The Wolverines have also been switching the guards up top against high ball screens, have seen their wings do a much better job of ‘bumping’ to the pass to the wing and then recovering back into their zone and have even executed some successful traps in the short corner.

Here’s a look at some of Michigan’s zone defense against Wisconsin:

The Goal: Defend the interior, prevent 1 on 1 mismatches and force the opposition to beat you from outside.

The Good: The 2-3 zone helps mask some of Michigan’s weaknesses defensively, both in terms of individual matchups and depth. Given the Wolverines’ mediocre post defense, the zone makes it more practical to eliminate that element of the game without throwing an array of complicated traps and double-teams that often times create breakdowns with such a young roster.

The Bad: Michigan lacks length at the top of the zone — although Muhammad-Ali Abdur-Rahkman is a solution to this problem — to make it the most effective. Playing two 6-foot guards, Spike Albrecht and Derrick Walton, at the top of the zone makes it easy for the opposition to pass or shoot over the top of the zone and can allow easy looks.

Bottom Line: I’ve thought Michigan’s 2-3 zones have left a lot to be desired in the past under John Beilein, but the 2-3 zone effort against Rutgers and Wisconsin was one of the best stretches I’ve seen. Rutgers is an easy team to zone, but Wisconsin isn’t and Michigan held in there with the 2-3 zone when the man-to-man defense was helpless.

1-3-1 Zone

Simply put, the 1-3-1 zone is a gambling defense. John Beilein rarely decides to go with the 1-3-1 zone unless Michigan is chasing a game. The 1-3-1 is designed to speed up the opposition and force them into uncomfortable shots, even if they are open. The Northwestern game was a great example of this as the Wildcats got a number of fairly open looks, but they weren’t necessarily in spots where they were used to play.

Here’s a look at every shot that Northwestern took against Michigan’s 1-3-1 zone, plenty of them were open but the Wildcats only managed nine points in 19 possessions against the zone.


The Goal: Speed up the opposition, change the pace of play and force turnovers.

The Good: The 1-3-1 is a great weapon to have. It takes the opposition out of their comfort zone and can be made effective with the correct lineup. The Wolverines also do a very good job of rebounding and running out of stops in the 1-3-1, which boosts its perception as a momentum-changer.

The Bad: Michigan isn’t actually forcing that many turnovers in the zone and misses Caris LeVert’s length at the top. There are plenty of teams in the Big Ten that can beat the 1-3-1 with ease (Ohio State, Wisconsin), but it’s still valuable weapon against some of the less disciplined offenses in the conference. It generally can only be played after a made basket and when beaten can result in very easy looks (corner threes, layups).

Bottom Line: The 1-3-1 zone is always going to be in John Beilein’s bag of tricks, but I’m not sure we’ll ever see it as Michigan’s primary defense. The Northwestern game was one of the first times I can remember Beilein ever running the 1-3-1 off of misses, but without Caris LeVert that plan may be out the window.

Going forward

Both zone defenses are here to stay. Michigan is low on bodies, low on experience and has some fundamental flaws defensively. By rotating between the man-to-man, 2-3 zone and 1-3-1 zone, Beilein has enough options to keep opponents off balance.

Michigan probably isn’t going to be a great defensive team this season, and it wouldn’t be surprising to see its defensive stats regress as the Big Ten schedule stiffens, but right now it’s clear that the zone defense has been effective.

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