Updated

Arizona Cardinals linebacker Daryl Washington has been suspended for the first four games of the 2013 regular season for violating the NFL Policy and Program for Substances of Abuse.

Washington is eligible to participate in offseason and preseason practices and games, but can't return to the active roster until the day after the Cardinals' fourth regular-season game.

"I was always taught that when you make a mistake, you admit it, learn from it and face whatever consequences there are," Washington said in a statement. "I take full responsibility and I understand that I let down my teammates, the organization and fans. I apologize for that and promise that no one will work harder to make up for it."

Washington, 26, earned his first Pro Bowl appearance last season after posting a career-high 134 tackles, nine sacks, two forced fumbles and an interception in 16 games.

A second-round pick in the 2010 NFL Draft, Washington has 319 tackles, 15 sacks, four interceptions and three forced fumbles in three seasons with Arizona.

"Adversity and dealing with it is part of the business but when it's avoidable like this was, it's particularly tough," said Cardinals head coach Bruce Arians, who was hired in January. "One of the biggest things we preach is accountability; Daryl knows that and our team knows that. We will deal with this and others will have to step up until he's back. I'm confident they will."