Wisconsin coach Bo Ryan is retiring effective immediately, he said after the team's win over Texas A&M-Corpus Christi.
Longtime assistant Greg Gard is taking over as interim head coach.
"After months of conversation with Barry Alvarez and his administrative staff, as well as my wife, Kelly, I have decided that now is the right time to step down from the head coaching position here at Wisconsin," Ryan said in a statement.
Ryan coached Wisconsin to a school-record 36 wins last season and a loss in the national championship to Duke. Wisconsin is 7-5 this season.
Ryan, who turns 68 next week, had said in a statement last June that he would coach this season and then step down.
"This was a decision months in the making," Ryan said. "I brought this up to Barry back in April. He advised me to take some time to think it over and I appreciated that. But in recent weeks, I have come to the conclusion that now is the right time for me to retire and for Greg Gard to have the opportunity to coach the team for the remainder of the season. I discussed this with Barry and I appreciate him giving me the space to make this decision."
Ryan is the winningest coach in Wisconsin history, with 364 wins over 14 seasons. He guided the Badgers to seven Big Ten titles and his 172-68 record (.717) in conference play is the best winning percentage in Big Ten history.