As soon as it became clear last winter that Nate Mason's steady attack was for real, Minnesota coach Richard Pitino began touting the freshman's offseason.

The key for the young guard's development, he said, would be his desire and effectiveness in getting stronger and building on a game that will be recognized and defended in a new way next season.

Mason now has eight weeks fewer to do so.

The rising sophomore injured his right thumb in an individual instruction last week, Pitino said Monday, and underwent surgery a couple of days ago. He's expected to miss two months.

"We weren't sure what was going to happen," Pitino said before downplaying the missed time.

Mason averaged 9.8 points and a 2.56-to-1 assist-to-turnover ratio in 26.1 minutes a game last year, starting for eight of those. He is the second-highest returning scorer and is expected to be a critical part of the 2015-16 team.

During the next eight weeks, Pitino said Mason will be riding the stationery bike and doing cardio to stay in shape, as well as working on different things with his left hand while missing all the team workouts and individual instruction.

That much lost time is never good for any player, especially one as fundamental to the Gophers' success as Mason. But Pitino pointed to Mason's steadiness, this time, as a reason to relax a little about the diagnosis.

"Everybody could use time to grow," he said, "but he had so much experience this regular season that missing two months won't be catastrophic.