Rex Kalamian, who served as Scott Brooks' lead assistant for two years with the Thunder will not be joining his staff in Washington, according to David Aldridge of NBA.com.
The Raptors' lead assistant was being courted by Washington and Houston, but opted to stay in Toronto with Dwane Casey, who received a three-year contract extension from the Raptors after leading them to the Eastern Conference Finals. It's also worth noting Casey and Kalamian previously worked together in Minnesota, when Casey was the head coach from 2005-07.
It's unclear who Brooks will try to target next, whether it's another former assistant from his days in Oklahoma City, or a well-regarded assistant outside of his circle.