49ers counting on Tramaine Brock to step up against Washington

The San Francisco 49ers have been losing key players in their secondary all year yet their defense hasn't skipped a beat.

That continuity gets another tough test this week without starting right cornerback Tarell Brown.

Brown left last week's game at New Orleans with a rib injury and hasn't practiced this week. He's unlikely to play Monday night when the 49ers (6-4) look to end a two-game losing streak against the Washington Redskins, the first game missed by a starter in San Francisco's secondary since the 2011 season.

But the 49ers are confident nickel back Tramaine Brock will step up in Brown's place, just like Brock stepped in for injured nickel back Nnamdi Asomugha earlier this season and became an impact player on the NFL's seventh-ranked defense who leads San Francisco with four interceptions.