Rob Lytle, an All-American running back at Michigan who scored a touchdown in the 1978 Super Bowl as a Denver Broncos rookie, has died. He was 56.

He died of a heart attack Saturday night in Fremont Ohio, Memorial Hospital spokeswoman Chasity O'Neill said Sunday. Lytle had been taken by ambulance to the hospital with symptoms of a heart attack, she added.

Lytle was drafted by the Broncos in the second round in 1977. He scored on a 1-yard run in Denver's 27-10 loss to Dallas in the Super Bowl. He played seven seasons with the Broncos and scored 14 times in the regular season.

``Rob was a teammate and an incredibly terrific guy,'' Michigan athletic director Dave Brandon said. ``When I heard the news this morning, I was sickened by it. It's a sad day because we've lost someone who was a great example of a Michigan man.''

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