Udoka will replace Celtics president of basketball operations Brad Stevens, who stepped down as coach earlier this month to replace Danny Ainge running the franchise's basketball operations.
Udoka, 43, separated himself quickly in the search process, sources said, and his candidacy was boosted with strong recommendations from key Celtics stars -- including Jayson Tatum, Jaylen Brown and Marcus Smart -- who played for Udoka on Team USA in the 2019 FIBA World Cup.
Udoka was an assistant with the San Antonio Spurs for seven seasons under coach Gregg Popovich. He left San Antonio to join Brett Brown's staff in Philadelphia two years ago and moved on to Brooklyn under Steve Nash this season. He spent several years in pro basketball as a player, including stops with the Lakers, Blazers, Kings, Knicks and Spurs.