CINCINNATI — The NFL rejected Antwan Odom's appeal on Friday and suspended the Bengals defensive end four games for violating its policy on performance-enhancing substances.

Odom was suspended before the start of the season but appealed, hoping to have the suspension reduced or eliminated. The league stuck with the full four games.

He would have likely missed the next couple of games anyway. Odom hurt his right knee during a 24-21 loss to Tampa Bay on Sunday and wore a brace this week. The Bengals (2-3) have their bye this weekend.

After the rest of the team worked out on Wednesday before dispersing, Odom said he would probably be sidelined for a game or two after the bye because of the knee injury. He'll be eligible to return from the suspension on Monday, Nov. 15 and would be eligible to play a home game against Buffalo the following Sunday.

Odom contended he didn't use a performance-enhancing drug. When the suspension was revealed in the preseason, he tweeted: "Yes, I tested positive for a banned substance but it wasn't steroids or (performance-enhancing drugs). More details to come but for now it's a league issue that's under appeal. Just know that I would never cheat to gain an edge in this game that I love."

The league doesn't reveal which substance was involved.

Odom tore his right Achilles' tendon last season, but made a full recovery and was ready for training camp. He has started three games and missed time with an injured left wrist. Odom led the team with eight sacks last season even though he played in only six games because of the injury.

He has no sacks and only eight tackles – tied for 12th on the team – this season.