Rivals Decoded Michigan’s Signals—and Shared Them With Another Big Ten Team

Two single-page documents, obtained by Sports Illustrated, listing detailed breakdowns of Michigan’s deciphered signals were shared last season with a Big Ten school set to face the Wolverines.

As a high-stakes showdown looms with Big Ten leadership, Michigan is aggressively fighting back against potential sanctions for alleged illegal signal-stealing by former football staffer Connor Stalions. Among the school’s means of rebuttal, it plans to formally present evidence to league officials that last season other Big Ten schools decoded the Wolverines’ signals and disseminated them to a future opponent.

A former Big Ten coach at a rival school in recent days forwarded to the Wolverines copies of two single-page documents listing Michigan’s deciphered signals, three sources with knowledge of the situation confirmed to Sports Illustrated. The former Big Ten coach was a member of a staff that he said last season received multiple detailed breakdowns of which signals corresponded to which play calls. He told Michigan, according to the sources, that the information had originally come from other Big Ten schools.

Harbaugh looked on intently during Michigan’s 41–13 pasting of Purdue in Ann Arbor on Saturday :: Rick Osentoski/USA TODAY Sports

The former coach shared the documents with Michigan in an attempt to show that signal-stealing is pervasive in the sport and to support embattled head coach Jim Harbaugh, a source familiar with the situation said. Harbaugh could face a suspension in the coming days from Big Ten commissioner Tony Petitti.

Copies of the documents were obtained by SI, with the information partially redacted because the Wolverines still run many of the same plays or use the same signals, a source familiar with Michigan’s play calls said. A source familiar with the contents of the documents verified their authenticity. 

The two Michigan signal breakdowns include sections devoted to deciphering the boards held up by staffers with images on them, lengthy lists describing hand signals for running plays, slightly shorter lists for passing plays and separate lists describing signals for play-action passes or bootleg plays. One of the documents also includes a section devoted to signals gathered during a 2022 game against the Wolverines, and both documents include a “2020 Game” heading, followed by a short rundown of signals ostensibly deciphered during a game that year.

A Michigan source confirmed that the signals described corresponded to their 2022 play calls. The Associated Press first reported that the former Big Ten staffer had told Michigan about its signals being decoded, but did not publish the specific documents.

The two documents listed out Michigan signals alongside play calls, many referring to staple running and passing plays. Both also included sections devoted to signals apparently collected during a 2020 game

The second of the two documents included headings apparently referring specifically to signals collected during a 2022 game, as well as ’20

In the documents, the signal descriptions are followed by what the actual plays are, many of which are staple runs or passes commonly found in many playbooks. “THROAT SLASH = GATOR” refers to the signaler making a throat slash motion, followed by a passing concept where one receiver runs a slot fade, while the other runs a hitch.

“CUT WRIST= SPL ZN” would refer to a signaler making a cut wrist motion, directing Michigan players to run split zone, a run concept where the offensive line blocks zone and a tight end comes back across the formation to block a backside defender.

Schools sharing signal information is not uncommon in college football, multiple sources in the coaching profession told SI, nor is it against NCAA rules. “Every week you call your friends on other staffs and say, ‘Hey, what you got [on our next opponent]?’” A current coach with Big Ten experience said. “Everyone does it. Who cares?”

Sign-stealing off television, or across the field during games, is allowed. What Stalions is accused of doing—orchestrating a network of associates to perform impermissible, in-person advance scouting and recording future Michigan opponents’ signals dozens of times—is in violation of the rules. The now former analyst resigned last week amid a controversy that has consumed college football.

A Naval Academy graduate, former Marine Corps captain and lifelong Michigan superfan, Stalions hung around the program for years before being hired full time by Harbaugh in 2022. He became known for his signal-stealing prowess, but said through his lawyer recently that no other Michigan staffer was aware of his impermissible scouting scheme. Harbaugh has said he knew nothing about what Stalions is alleged to have done and would never condone such activity.

The NCAA is investigating, but that will be a drawn-out process that stretches well into 2024. The rest of the Big Ten has voiced its anger to Petitti about being allegedly spied upon by Michigan and urged the commissioner to act. The Wolverines are ranked No. 2 in the AP poll and are undefeated with their two biggest games of the season left to go, at Penn State on Saturday and home against fellow unbeaten and bitter rival Ohio State on Nov. 25.

This information is likely to be part of what is presented to the Big Ten.

Michigan is also likely to argue that there is a distinction without a true difference between what Stalions is accused of doing and what other Big Ten schools did in forwarding their scouting to a future opponent. In the process of making that argument, Michigan seems ready and willing to throw blame around the rest of the conference, potentially escalating this into a bitter battle on many fronts. Michigan will also likely point to a lack of due process involved with suspending Harbaugh before an NCAA investigation wraps up.

One front that was de-escalated Monday: NCAA sources confirmed to SI that it has found no connection between Ohio State coach Ryan Day or his family and the original information that was received by the association in October, sparking the investigation. Yahoo first reported that no connection had been found.

Petitti is facing the difficult task of finding an appropriate punishment in an unprecedented situation, and without much clarity within the Big Ten bylaws. All while Big Ten and NCAA investigations are still in motion. However, sources familiar with the Michigan program told SI that the school is bracing for Petitti to levy punishment.

“Tony told Michigan this was the worst scandal in Big Ten history, not including game-fixing,” one Big Ten administrator told SI.

It’s up to the commissioner to find a way forward for Michigan and the whole conference—a job that may be about to get a lot harder.

Editors’ note: This story was updated on Tuesday, Nov. 7, to include images of the documents listing the Michigan signals, as well as additional explanation of them.