RICHMOND, Va. -- Jarvis Jenkins is the eighth Washington Redskins player to receive an NFL drugs-related suspension in 22 months, sanctioned for four games without pay Friday for testing positive for a banned performance-enhancing substance.
Expected to start at defensive end, Jenkins will instead miss the first four games of the regular season. He will be eligible to return to the active roster on Sept. 30, following the Week 4 game against the Oakland Raiders.
Jenkins, who was on the practice field at training camp working with the first-string unit when the suspension was announced, released a statement saying he was "shocked and confused" to learn that he had tested positive for what he called "an obscure substance." Then he addressed reporters at length following the practice, apologizing to fans, the team and his parents.
"It was a simple mistake," he said, "but I'm accepting my responsibilities like a man."
Jenkins said he takes pre-workout and recovery supplements. Every NFL player has been instructed not to take supplements that don't have an "NSF" label -- a label that means they've been certified as acceptable under an agreement between the league and players' union -- but Jenkins said he nevertheless took an over-the-counter supplement that didn't have the label.
Jenkins said he checked the ingredients of the supplement, but he learned that's not a fail-safe method. In March, he was informed that he had tested positive for a substance women take for breast cancer and that has also been used by athletes in connection with steroids.
He appealed the suspension, but the league ruled against him.
"I thought I was going to get off on it, and I didn't," he said. "The NFL has strict rules. ... They tell us we're responsible for what's in our body. Obviously I'm being led as an example."
Jenkins' backup was expected to be Adam Carriker, but Carriker had a third surgery Thursday for a right knee injury and is unlikely to play this season. Chris Baker, who has been moved from nose tackle, and Kedric Golston are the leading candidates to start while Jenkins is away. Jenkins is allowed to practice during training camp and can play in preseason games.
Jenkins said the Redskins do a good job of educating players about the NFL's drug policies, but the results are debatable. Left tackle Trent Williams, tight end Fred Davis and cornerback Phillip Buchanon served four-game sanctions in 2011. Cornerback Cedric Griffin and tackle Jordan Black were docked four games last year.
Each suspension comes with its own backstory -- Williams, Davis and Jackson were sanctioned for substance abuse, the rest for performance-enhancing drugs -- but coach Mike Shanahan acknowledged the troubling trend.
"We have emphasized it," Shanahan said. "But maybe not enough."
A second-round pick in 2011, Jenkins missed his rookie season with a right knee injury. He returned last year to start 14 games and felt primed for a breakout season.
"It's always a tough blow for your football team," Shanahan said. "Hopefully our players will learn that without the label of NSF, you can't take any supplements, because you never know what's going to be in the supplements. We'll pay the price for it. Hopefully our players will learn from it."