Head coach Mark Dantonio announced the dismissals Tuesday night in a one-sentence statement. Both players have been removed from the team roster on Michigan State's official Web site.
Winston was suspended from the team last year following his role in an off-campus fight that left Michigan State hockey player A.J. Sturges seriously injured. The sophomore running back from Detroit served four months in jail for misdemeanor aggravated assault but was reinstated to the team in August on the same day as his release.
He earned a starting job this fall before suffering a season-ending knee injury Oct. 10 against Illinois.
Jenrette, a safety, appeared in five games this fall for Michigan State before suffering a broken foot Oct. 3 against Michigan.
Adam Rittenberg covers Big Ten football for ESPN.com. He can be reached at firstname.lastname@example.org.