The Toronto Raptors have reached an agreement in principle to hire Dallas Mavericks

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assistant Dwane Casey as their next head coach, according to multiple league sources. Casey’s hiring has not been formally announced by Toronto yet, but is expected to happen anytime between Tuesday and Thursday nights’ NBA draft. Casey is the Mavericks top assistant coach and a defensive architect, and he will be tasked with the job of replacing Jay Triano and turning around a franchise that finished 30th in the league in defensive efficiency last season, allowing 110 points per 100 possessions. The Mavericks, under Casey’s tutelage, finished seventh in the same category last season at 102.3 points per 100 possessions.

Toronto narrowed its search down for Triano’s replacement to just two coaches in former Minnesota Timberwolves head-coach and current Boston Celtics assistant coach Lawrence Frank, but ended up zeroing in on Casey shortly after the NBA finals. Casey had been Rick Carlisle’s assistant and defensive coordinator for the past three years and the team’s rechim a hot commodity. Every team that had a vacant head coaching position contacted Casey this season and he was even a finalist for the Houston job before Kevin McHale was hired. It will be the 54-year-old Casey’s second shot at being a head coach after being dismissed by the Timberwolves with a record of 20-20 during the 2006-07 season.