Floyd Youmans, the troubled Montreal Expos pitcher who underwent alcohol rehabilitation last fall, was suspended indefinitely by the commissioner's office Saturday "for failing to comply with his drug testing program."

Although Commissioner Peter Ueberroth confirmed that Youmans had been undergoing "periodic drug testing," his office would not say how Youmans had violated the program.Youmans had been scheduled to pitch Saturday night against Pittsburgh.

In a brief statement, Ueberroth said the suspension "is indefinite pending further evaluation."

On March 30, Ueberroth suspended Eddie Milner of the Cincinnati Reds after he admitted using cocaine. Milner, who had undergone rehabilitation last season, returned to action on June 19.