Seattle Seahawks defensive end Bruce Irvin has been suspended for the first four games of the 2013 season after the league announced he violated the NFL policy on performance-enhancing substances. The NFL announced the decision Friday. Irvin will be eligible to participate in all offseason activities and preseason practices and games, but will be suspended without pay for the opening four games. Irvin will be eligible to return to Seattle's active roster on Sept. 30 following the Seahawks' Week 4 game at Houston. In a statement sent by the team, Irvin says he took a substance prohibited by the NFL without a medical exemption. He will not appeal. Irvin was expected to start at defensive end with Chris Clemons likely to miss the start of the season while recovering from knee surgery.