Story byTony Garcia, Detroit Free PressWed, January 7, 2026 at 5:47 PM UTC·2 min readMichigan football has suffered its biggest loss to date in the transfer portal. Cole Sullivan, a sophomore linebacker who was one of the team's top defensive players in 2025, has committed to Oklahoma, according to multiple reports. Sullivan had 44 tackles in his first season as a key defensive player under Wink Martindale, including five for loss and two sacks. AdvertisementAdvertisementAdvertisementHe also had a nose for the ball, recording four pass breakups, leading the team with three interceptions, forcing a fumble and coming away with a fumble recovery. Michigan linebacker Cole Sullivan (23) celebrates an interception against Washington during the second half at Michigan Stadium in Ann Arbor on Saturday, Oct. 18, 2025. In 2024, Sullivan was named the team's special teams rookie of the year, playing in all 12 games and recording four tackles.