Knight, 30, is 6-foot-2 and appeared in five games with the Mavs for the season. He signed his second 10-day deal on March 29.
He has spent time with the Pistons, Bucks, Cavaliers, Rockets and Suns since entering the league as the No. 8 overall draft pick in 2011. Overall, Knight has appeared in 446 games.
With the Mavericks, he averaged 6.4 points and 1.6 assists. He will now re-enter free agency and if not picked up by another team this weekend, will enter the pool of unrestricted free agents that can start signing in July.