Coach Joe Paterno said Tuesday that he doubts Green will return this fall. Green is no longer listed on Penn State's roster.
"I think it's best for him and the team if he steps away for a while," Paterno said.
Green backed up Evan Royster for the past three seasons, recording 1,085 rushing yards and eight touchdowns on 224 attempts in his career. Despite injury problems and the rise of sophomore Silas Redd last season, Green was expected to compete for the starting job this summer.
Redd and junior Brandon Beachum have been Penn State's top two running backs in camp.
Adam Rittenberg covers the Big Ten for ESPN.com. He can be reached at firstname.lastname@example.org