Toronto Raptors coach Dwane Casey has reached agreement on a three-year, $18 million contract extension, league sources told The Vertical.

The Raptors essentially tore up the 2016-17 option on Casey's deal and replaced it with a new three-year contract that runs through 2018-19, league sources said.

Under Casey, the Raptors had the franchise’s best season in history, which included 56 regular-season victories and a berth in the Eastern Conference finals. Toronto lost 4-2 in the best-of-seven series against Cleveland.

Casey finished fifth in the voting for NBA Coach of the Year in 2016.

In his five seasons as Raptors coach, the franchise has improved its victory total every season, including three straight playoff appearances. The development of DeMar DeRozan and Kyle Lowry into All-Stars has been paramount to the success of Casey’s program.

The Raptors have been working to hold together his coaching staff too, including assistant coaches Andy Greer (Minnesota and New York) and Rex Kalamian (Washington) who are the objects of interest elsewhere, league sources said.

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