FRISCO (CBSDFW.COM) - Dallas Cowboys defensive lineman David Irving has been suspended for the first four games of the 2018 regular season for violating the NFL's substance abuse policy, according to a league spokesperson.

Irving will be allowed to participate in all offseason and preseason practices and games.

He will be eligible to return to the team's active roster on Monday, October 1 after the Cowboys' game against the Detroit Lions.

The defensive lineman was suspended last June for the first four games of the 2017 regular season for violating the NFL's performance-enhancing drug policy.

Dallas will open up its regular season on September 9 against the Carolina Panthers.