The Boston Celtics made a significant commitment to lure Brad Stevens to the NBA as coach, giving him a six-year, $22 million contract, sources told Yahoo! Sports.

Stevens, 36, left the comfort and security of a 10-year deal at Butler to replace former coach Doc Rivers and oversee the Celtics rebuilding process.

Boston general manager Danny Ainge had long been fond of Stevens and made a swift, decisive courtship to convince him to become his coach, sources said.

Before securing Stevens' interest and commitment to Boston's head-coaching job, Ainge talked informally about the position with popular former Celtic Brian Scalabrine, sources told Y! Sports.

Ainge believes Scalabrine — who is strongly considering an assistant coaching job with the Golden State Warriors — has a future in coaching and talked in broad terms about the job with him, sources said. Nothing ever advanced to a formalized interview, though.

Ainge also considered Celtics assistant coach Jay Larranaga, too, and the two sat down on a couple of occasions recently to discuss the head-coaching job, sources said. Before leaving for the Los Angeles Clippers, Rivers had given Larranaga a strong endorsement for Boston's head coaching job, sources said. Ainge and Suns GM Ryan McDonough — a Celtics assistant GM this past season — each believe Larranaga is a future head coach in the NBA.

After playing overseas for 12 years, Larranaga has one year experience in the NBA with the Celtics and two successful seasons as an NBA D-League head coach on his resume. He'll coach the Celtics summer-league entry in Orlando, and Ainge may still try to convince him to stay on Stevens' staff despite a standing offer to join Rivers with the Clippers, sources said.

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