The person requested anonymity because the deal has not been announced.
Mosley will replace Steve Clifford, who parted ways after leading the team for three seasons and two playoff appearances, both first-round exits.
Later Sunday, the Magic confirmed the news in a release.
“We would like to welcome Jamahl and his family to the Magic family,” Orlando president of basketball operations Jeff Weltman said. “Within the NBA coaching community, Jamahl is considered a rising star. His coaching path is rooted in player development. He is a communicator and connector, and we look forward to him leading our group.”
The Athletic first reported the news.
This season, the Magic went 21-51, the second-worst record in the Eastern Conference.
The 42-year-old Mosley spent the last seven seasons with the Mavericks under Rick Carlisle. He also was an assistant with the Cleveland Cavaliers and Denver Nuggets.
Orlando will look to upgrade a young roster with two lottery picks, including the fifth overall selection, in the NBA draft later this month.
This article originally appeared on USA TODAY: Jamahl Mosley, Mavs assistant, to be hired as Magic's head coach