Seattle Seahawks cornerback Brandon Browner will start his 4-game suspension for violating the league’s policy on performance-enhancing drugs.

Browner chose not to appeal the positive test, reportedly for Adderall, and will miss the final 4 games of the regular season.

Browner was not at practice last Wednesday and isn’t eligible to be at the team facility until his suspension ends. If the Seattle Seahawks make the playoffs, he will be eligible for the postseason. Scores

Walter Thurmond, who was a starter for a short time in the 2011 season before suffering a leg injury, will step in and take Browner’s position.

“I’ve thought all along that we are very lucky to have Walter with some background which has started for us in the past,” Seattle Seahawks coach Pete Carroll claimed. “He’s a good athlete. He played very well for us this last week and he’ll step right up into that mode.”

Richard Sherman, the Seahawks’ other starting corner, is following his appeal of his 4-game PED suspension, also reportedly for Adderall. The appeal is expected to be heard December 14.

If he loses the appeal, league sources believe Sherman would miss the last 2 games of the regular season and the 1st two games of the playoffs, if the Seattle Seahawks make the postseason and advance.

Any games remaining on Sherman’s suspension will carry into 2013.

“I’m still not commenting about it, but I’m disappointed when we lose anyone by injury or whatever. These guys work so hard to be here and all of that and you come to rely on guys and when you lose guys, it’s always disappointing,” Carroll declared. “But actually where the focus goes for us is right to the men who are stepping up. … It’s like he got injured is truly what it adds up to and on we go.”

Any player who is suspended for violation of the PED policy also is ineligible for the Pro Bowl.

Browner has 44 tackles, 3 interceptions and 6 passes defensed this season. He is in his 2nd season with the Seahawks after getting pulled from the Canadian Football League as he fit the mold of what Carroll wants: big, physical cornerbacks who can play man coverage.

He was voted as a Pro Bowl alternate in his 1st NFL season, and ended up playing in the game. Last season he had 54 tackles and 6 interceptions, 2 of which were returned for touchdowns.

Browner is the f4th Seahawks player to be suspended for a PED violation during the past calendar year, joining John Moffitt, Allen Barbre and Winston Guy.

“I’ve been disappointed about the whole situation, it’s something that he had to deal with it and we had to deal with it, but there is nothing we can do at this point,” Carroll said.

Thurmond has played in only one game during the past 13 months, that coming last week in Chicago when he took control of as Seattle’s defensive back in nickel situations with veteran Marcus Trufant out with a hamstring injury. Thurmond played in 6 games and started 3 during the 2011 season before suffering a broken ankle at Cleveland.