RENTON — Cornerback Brandon Browner began his four-game suspension sooner with an eye toward being available later this season.

Whether that happens will depend on how the Seahawks cope with the absence of their starting cornerback, who will miss the final four regular-season games for violating the league’s policy on performance-enhancing drugs. Walter Thurmond will start in Browner’s place beginning Sunday against Arizona.

If the Seahawks reach the postseason, Browner would be eligible for the playoffs.

Coach Pete Carroll declined to comment on Browner’s case, but said, “I’m disappointed that we’d lose anybody whether it’s by injury or whatever.”

Browner’s suspension is the first step toward resolving the issue that has loomed over the Seahawks for the past 10 days. On Nov. 25, reports surfaced that Browner and fellow starting cornerback Richard Sherman tested positive for a banned substance and could face four-game suspensions. Several reports said that the banned substance for both players was an amphetamine in Adderall, a prescription drug used to treat Attention Deficit-Hyperactivity Disorder (ADHD). The NFL and Seahawks won’t comment.

Sherman, the other half of the Seahawks’ tall, physical cornerback tandem, remains eligible to play. His hearing is scheduled for Dec. 14.

Browner dropped his appeal, thereby beginning the suspension this week and insuring that Seattle isn’t at risk of missing both of its starting cornerbacks for the same four games. It also means that if Sherman is suspended, the Seahawks won’t be missing both players if the team reaches the postseason. Seattle (7-5) would qualify for the playoffs as an NFC wild card if the season ended now.

Thurmond will start in Browner’s place at right cornerback with rookie Jeremy Lane expected to be play when Seattle uses formations with five defensive backs.

Veteran Marcus Trufant did not practice Wednesday because of a hamstring injury that caused him to miss Sunday’s dramatic overtime road victory over the Chicago Bears.

“The focus goes for us right to the guys who are stepping up,” Carroll said.

That was how Seattle approached the situation last month when K.J. Wright suffered a concussion and was replaced by Mike Morgan and Sunday in Chicago when Malcolm Smith stepped in for Leroy Hill, who was unable to play because of a sore ankle.

Seattle s taking the next-man-up approach with regard to Browner’s spot.