One day after his DWI arrest, the Rangers were set to reinstate reliever Jeremy Jeffress from the restricted list Saturday, but Major League Baseball blocked the move, reports Evan Grant of the Dallas Morning News. The league took action because it’s concerned that drugs may have been involved, per Grant, who adds that it’s awaiting the results of a blood test administered to Jeffress after his arrest.

Jeffress had a blood alcohol content of .115 at the time of the arrest, and police found a clear plastic bag with a “green leafy substance believed to be marijuana or a synthetic cannabinoid” in his car’s glove box, the arrest warrant states. Jeffress denied that the substance was his, but he was hit with multiple suspensions for marijuana usage during his minor league career. Notably, positive tests for marijuana do not result in suspensions in the majors.

In a recent interview with T.R. Sullivan of MLB.com, Jeffress attributed his past marijuana dependence to epilepsy, which he has dealt with since his teenage years.

“I was self-medicating … doing it with marijuana. It would help, but at the same time, the rules and regulations of baseball wouldn’t allow it. I had to find out other ways to deal with it,” said Jeffress, who was one marijuana suspension away from a lifetime ban in the minors.

FOX Sports’ Ken Rosenthal reported in May that the Brewers helped Jeffress overcome his marijuana issues, but they traded the 28-year-old to the Rangers in advance of the Aug. 1 non-waiver trade deadline. Prior to his arrest, Jeffress tossed nine innings with Texas and allowed four earned runs on seven hits and five walks. He won’t return to the Rangers’ bullpen until the league consults with the players’ association and declares him eligible, according to Grant.