As a sophomore in 1958–59, Wiesenhahn was a starting forward on the nationally ranked team led by Oscar Robertson.

Wiesenhahn averaged 6.2 points and 6.4 rebounds per game as the 26–4 Bearcats won the Missouri Valley Conference (MVC) title and advanced to the NCAA Final Four, where they finished in third place nationally.

The Bearcats posted a 28–2 record, won the MVC title and again advanced to the Final Four, but they again had to settle for third place.

[3] the Bearcats advanced to the NCAA national championship game against Ohio State, and Wiesenhahn would be guarding future Hall-of-Famer John Havlicek.

The Bearcats, led by starters Wiesenhahn, Tom Thacker, Tony Yates, Paul Hogue, and Carl Bouldin, defeated the heavily favored Buckeyes, 71–65 in overtime to claim the national crown.