Milwaukee Bucks forward Bobby Portis has been suspended for 25 games for taking a banned substance, the NBA announced on Thursday. Portis tested positive for a painkiller called Tramadol, and will begin his suspension on Thursday when the Bucks host the Los Angeles Clippers. He will be eligible to return on April 8 against the Minnesota Timberwolves, just four games before the end of the regular season.

Portis’ agent told Shams Charania in a statement that the positive test was the result of a medication mix-up. “I am devastated for Bobby right now because he made an honest mistake and the ramifications of it are incredibly significant,” Mark Bartelstein said. 

Portis, a fan favorite in Milwaukee, is averaging 13.7 points, 8.3 rebounds and 2.2 assists per game, while shooting 36.4% from 3-point range. His absence will be a significant blow to the Bucks’ second unit as they fight for playoff seeding in the second half of the season. 

CBS Sports will have more on this story.