Cowboys linebacker Rolando McClain has been suspended for the first four games for violating the NFL's substance abuse policy.
The league said in a statement Thursday that McClain would be suspended without pay and eligible to return for Dallas' Week 5 game against New England.
McClain issued the following apology Thursday afternoon:
"I apologize to my family, the Cowboys organization, my teammates and Cowboys fans for my mistake. I will not break the rules of my profession in the future, and I regret my error. I look forward to returning to the field on week 5, when I hope to help my team beat the Patriots."
McClain can participate in training camp and all four preseason games.
The suspension leaves the Cowboys without two key defenders to start the season. Defensive end Greg Hardy was suspended for the first 10 games for his role in a domestic violence case. Hardy is appealing the suspension.
McClain sat out the 2013 season and twice walked away from football before reviving his career with a solid season for the Cowboys last year.