According to ESPN, DeRozan has been fined $25,000 for "recklessly throwing the basketball toward a game official and into the spectator stands."
After DeRozan and his team jumped into an early double-digit lead, the Spurs found themselves down by 18 midway through the fourth quarter. In an effort to not let the game slip out of control, DeRozen made a hard move to the basket and collided with the Nuggets' Gary Harris. The 50/50 call did not go the Spurs way as DeRozan was called for the offensive foul. DeRozan, not happy with the call, threw the ball towards referee Scott Foster.
Although the ball didn't make contact with the official, it was clear that the move was done out of frustration. This led to DeRozan being ejected from the game as well as receiving the subsequent fine.
Denver's 117-103 victory ties this heated first-round series at 2-2. Fortunately for the Spurs, the NBA figured that the fine and ejection were enough punishment for DeRozan and decided not to tack on any extra penalties. This means that San Antonio will have their starting shooting guard on Tuesday for Game 5 in Denver.