Jonathan Kuminga made huge strides during the 2023-24 NBA season, but the third-year forward wasn't eligible for the Most Improved Player award.
Leonard missed the last eight games of the regular season and Game 1 against the Mavericks with knee inflammation.
Tyrese Maxey gained the title of the NBA's Most Improved Player on Tuesday night.
76ers guard Tyrese Maxey earns 319 points to White's 305 in close vote