Hitler's despicable image made a surprise appearance at a Michigan State University football game ... and not surprisingly the reaction was collective disgust, leading to the college issuing a mea culpa.

The Nazi leader's ugly mug flashed on a huge video board overlooking Spartan Stadium Saturday night ... just before the MSU Spartans kicked off their match-up against the Michigan Wolverines.

The large screen displayed not only the Fuher's photo but also a trivia question about his birthplace in Austria.

Of course, the screwup didn't sit well with many people amid the Israel-Hamas war -- so they snapped pictures of Hitler's cameo and posted them on social media.

It didn't take long for MSU officials to apologize, while also blaming the fiasco on a "third-party source."

In a statement, MSU's Associate Athletic Director Matt Larson said, "MSU is aware that inappropriate content by a third-party source was displayed on the video board prior to the start of tonight's football game."

Larson continued, "We are deeply sorry for the content that was displayed, as this is not representative of our institutional values."

He also promised to never again use the third-party source, while implementing "stronger screening and approval procedures for all video board content in the future."