Coach Bret Bielema announced the news Monday, two days after the Badgers' 16-13 overtime loss to the Spartans. Doctors determined the redshirt freshman would not need surgery to repair the injury.
"It probably will be an eight-week recovery, which takes him out of the regular season," Bielema said. "There is an outside chance of something for the postseason, but that would be right on the edge of it. And everything, if it goes to plan, he should be 100 percent to go for spring ball. The good news is he's a freshman, so we have three years of eligibility remaining with him."
Stave completed 70 of 118 attempts for 1,104 yards and six touchdowns in seven games. He threw three interceptions.
He was the top quarterback in spring practice, but junior transfer Danny O'Brien earned the starting slot in fall camp ahead of Stave and fifth-year senior Curt Phillips. Stave replaced O'Brien in the second half of Wisconsin's 37-26 victory against UTEP on Sept. 15 due to a handful of turnovers by O'Brien, and Bielema named Stave the starter going forward.
O'Brien and Phillips will vie for the starting spot for Wisconsin (6-3, 3-2 Big Ten), which has a bye week before playing Indiana (1-3, 3-5) on Nov. 10 in Bloomington. Freshman Chase Knox will be the Badgers' third option at the position.
O'Brien and Phillips will split snaps working with the No. 1 offense in practice this week and Bielema will choose a starter on Sunday, but won't announce his decision until early next week.
"Danny's had his shot a couple times this year," Bielema said. "We'll take this bye week and pretty much give him and Curt equal reps and see where we're at on Sunday."
O'Brien completed 52 of 86 attempts for three touchdowns in six games. He relieved Stave in the third quarter against Michigan State, completed 5 of 11 passes for 44 yards and was sacked three times.
Phillips was inserted for three plays in one series during the second quarter of the Badgers' 31-14 win against Illinois on Oct. 6. Prior to that appearance, he had not played in a game since the 2009 regular-season finale.
Phillips, who has undergone surgery three times to repair anterior cruciate ligament injuries to his right knee, has improved in regular-season practice despite slow progress in fall camp. He picked up pace during fall sessions when the Badgers practiced twice daily, and Bielema and offensive coordinator Matt Canada are pleased with Phillips' development.
"I would think he's actually gotten better with a limited amount of practice time," Bielema said. "There's probably not a kid that's invested more time to get on the field than Curt Phillips. Matt has been intrigued with Curt ever since day one. He's got that `it' factor that quarterbacks need to have. It will be fun to see him really compete this week."