FLORHAM PARK, N.J. -- New York Jets linebacker Brandon Copeland, coming off his best NFL season, was suspended without pay for violating the NFL's policy on performance-enhancing drugs, the league announced Wednesday.

Copeland is allowed to practice and play in the final two preseason games. After that, he can't return to the roster until Oct. 7, the day after the Jets' Week 5 contest against the Philadelphia Eagles. New York's bye falls in Week 4.

Copeland, 28, posted on Instagram that a supplement he took "was contaminated with a banned substance" that wasn't listed on the label.

This has been a tough week for the Jets' linebacking corps, as starter Avery Williamson suffered a season-ending knee injury in the second preseason game.

Copeland, playing with his fourth team, emerged as a regular on defense last season for the Jets. He finished with a career-high five sacks. He didn't attract a lot of interest in free agency and wound up re-signing with the Jets for one year at $1.75 million, including a $250,000 signing bonus.

The new coaching staff changed his position, making him an off-ball linebacker in certain packages. His playing time has been inconsistent in the preseason, leading to speculation about his roster status.

Copeland was used in the fourth quarter last week against the Atlanta Falcons, fueling talk about him being on the bubble. But in two practices this week, he was spotted in certain first-team packages.

The Jets, perhaps anticipating the suspension, signed linebacker Stephone Anthony on Tuesday night. Anthony, a 2015 first-round pick of the New Orleans Saints, played the past two seasons under coach Adam Gase with the Miami Dolphins.

Without Copeland, the Jets' top outside linebackers are starter Jordan Jenkins, plus backups Frankie Luvu and Tarell Basham. Rookie Jachai Polite, a third-round pick from Florida, has been a nonfactor.

Copeland will join tight end Chris Herndon on the suspended list to start the season. Herndon will sit four games because of a substance-abuse violation.

Copeland gained a measure of celebrity in the offseason as a co-professor at his alma mater, the University of Pennsylvania. He taught a course called "Life 101," which supplied students with financial information. He was featured by ESPN, The Wall Street Journal and the "Today" show, among other media outlets.