Note: This story has been updated with the information that the victim of the assault is a U-M student.

The rivalry between Michigan State University and the University of Michigan escalated into violence in Ann Arbor Sunday.

It's usually a friendly rivalry, but the Michigan-Michigan State rivalry turned violent in Ann Arbor Sunday morning.

According to police, a man punched a Michigan State University fan, and U-M student, who was yelling the East Lansing school’s cheer “Go Green, Go White”, several times early Sunday morning, sending him to the hospital.

University of Michigan police reported responding at 4:43 p.m. Sunday to the University of Michigan Hospital’s emergency room after a man reported an assault.

The victim told police he was on The Diagonal, 900 block of North University Avenue, about 2 a.m. Sunday. He and another friend were yelling "Go Green, Go White" when they were approached by two men.

One of the men punched the victim several times, according to police.

The Michigan State fan did not immediately go to the hospital to seek treatment.

University of Michigan police spokeswoman Diane Brown said Monday the person yelling "Go Green Go White" was actually a University of Michigan student.

The suspect is described as a white man, 18 years old, 6-feet-4 inches tall, 200 pounds, with a large and muscular build and wearing a plaid shirt.

Anyone with information on this incident is encouraged to call the University of Michigan police at 734-763-1131.

Kyle Feldscher covers cops and courts for The Ann Arbor News. He can be reached at kylefeldscher@mlive.com or you can follow him on Twitter. Find all Washtenaw County crime stories here.