When Holtz moved on to New York Jets of the NFL in 1976, Rein became the youngest college football head coach upon his hiring by North Carolina State. Guiding the NC State Wolfpack football team, Rein was an advocate of the coaching philosophy of Ohio State's Woody Hayes for whom Rein played. During Rein's four years at NC State, he led the team to two bowl games, defeating Iowa State in the 1977 Peach Bowl and defeating Pittsburgh in the 1978 Tangerine Bowl. In Rein's final year at NC State, his team won the Atlantic Coast Conference championship. However, it was not invited to a bowl–to date, the last power conference champion to be left out of a bowl game.