The incident occurred during the third quarter of Toronto's game against Portland. After Portland's J.J. Hickson made a free throw, Johnson attempted to grab the rebound. He and referee David Jones both pulled at the ball and after appearing to have words, Jones ejected Johnson from the game.
Johnson, who said he was upset he wasn't given a reason for his ejection, had to be held back by teammates. While being escorted off the court, Johnson threw his mouthpiece at Jones, hitting him in the back. Johnson will be suspended without pay and will miss Toronto's game against the Brooklyn Nets on Wednesday.
The 25-year-old Johnson has played a reserve roll for the Raptors this season. He's averaged 7.1 points and 5.4 rebounds per game off the bench.