Michigan State basketball spokesperson Matt Larson confirmed the injury Friday night.
The sophomore averaged 12.9 points per game during his freshman season and was named the Big Ten freshman of the year.
He suffered from shoulder injuries through much of his freshman season. He opted not to have surgery this offseason and went through rehab instead.
The Spartans begin practice for the 2013-14 season in four weeks. MSU will open the season with an exhibition against Grand Valley State on Oct. 29 before the regular season begins on Nov. 8 against McNeese State.