After narrowing the list to three finalists, the Magic extended an offer to Hennigan on Wednesday, sources said.
Former New Orleans Hornets GM Jeff Bower and San Antonio assistant GM Dennis Lindsey were the other two finalists for the job.
Hennigan, 30, will become the youngest GM in the NBA.
Hennigan flew to Grand Rapids, Mich., for a second time in a week in recent days to meet with members of the DeVos family, who own the Magic. Hennigan made a rapid rise through the San Antonio Spurs and Thunder organizations. He is currently the Thunder's assistant GM for player personnel. Orlando president Alex Martins wants to mimic the Thunder organization’s excellent track record of drafting, player development and creating a winning culture.
Hennigan will immediately be confronted with making a decision on All-Star center Dwight Howard’s future. Howard is signed through the 2012-13 season, but another fallout with management has left him wanting a trade soon. Howard will push for a trade to the Brooklyn Nets before the June 28 NBA draft to clear the way for Nets free agent Deron Williams to re-sign with the Nets and partner in the new Brooklyn arena next season.
Hennigan will focus on Howard's future and the draft as his first priorities, and won't fully engage a coaching search to replace Stan Van Gundy until after the draft, sources told Yahoo! Sports.