For his sophomore season, Diane was named to the preseason All-Big West team. However, he was ruled academically ineligible for the first semester by the NCAA. At the close of the regular season, Diane was awarded his second straight conference Player of the Year honor. He averaged 25.6 points, 10.2 rebounds, two blocks and 1.7 steals per game. Following the season Diane declared for the 2020 NBA draft.
