Before the suspension, the Denver Post reported in its Tuesday editions that the suspension was coming. Anderson confirmed to the newspaper that he tested positive for marijuana, yet insisted he inhaled nothing more than second-hand smoke.
"I'm very saddened by the decision made by the NFL," Anderson told the paper. "I know this has a tremendous negative impact on my team, my coaches, my family and fans. I have no choice but to live with the decision and come back for the last three games. I want to apologize to my fans and the entire community for this humiliating and embarrassing situation."
Anderson will miss a key four-game stretch, including currently unbeaten AFC West leader Kansas City on Dec. 7. He has 198 yards on 50 carries this season.
He is eligible to return Dec. 14 against Cleveland.