Michigan had traveled to Berkeley that day to play the California Golden Bears. Harmon was tearing them up, returning the opening kickoff 94 yards for a touchdown. He later scored on a 72-yard run, and a fan named Harold Brennan, who had been tossing back a few cocktails, had seen enough of Harmon making fools of the Bears.
When Harmon broke free on another long run and headed toward the end zone, Brennan took matters into his own hands, running onto the field to stop Harmon. Check the video to see what happened.