Connor Stalions. Adam Cairns/Columbus Dispatch / USA TODAY NETWORK

Central Michigan University has not been able to determine whether Connor Stalions was on its sideline for a game earlier this season, and the NCAA has now joined the investigation.

In a statement to ESPN’s Adam Rittenberg on Monday, CMU athletic director Amy Folan said the school is still working to uncover the identity of the man resembling Stalions who was on the Chippewas’ sideline for their Sept. 1 game against Michigan State. Folan said the review has continued “in cooperation with the NCAA.”

Some photos went viral last week that showed a person who resembles Stalions wearing Chippewas gear on the CMU sideline during the team’s 31-7 loss to Michigan State. Folan said last Tuesday that CMU is investigating the photos.

CMU head coach Jim McElwain also addressed the situation, and his comments made it seem he suspects the individual was Stalions.

The idea of Stalions infiltrating another team’s sideline to spy on one of Michigan’s future opponents initially sounded farfetched. However, the longer the investigation goes, the more likely it seems that Stalions was the person in the photos. If it were someone else, CMU likely would have figured it out by now and/or the person would have come forward.

Stalions was suspended with pay before he resigned from his job on Friday. There has been mounting evidence supporting the claims that he illegally stole signals from opponents, which could lead to significant disciplinary action for Jim Harbaugh.

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