Heading into this offseason, one of the key storylines for the San Francisco 49ers was going to be how it handles its situation at cornerback.
Friday, the team took a step toward answering that question by extending Tramaine Brock's contract for four years and $16 million, according to multiple reports.
Brock was initially slated to fight for a roster spot heading into training camp after the team signed veteran Nnamdi Asomugha. A season-ending ACL tear to Chris Culliver elevated Brock up the depth chart, but he still found himself as the team's No. 4 corner at the start of the regular season.
But when Asomugha went out with a knee injury in Week 3's loss to the Colts, Brock stepped in a played well in his absence. Since taking over as the team's primary nickel corner, Brock leads the team with four interceptions - including one returned for a touchdown in his NFC Player of the Week performance Oct. 6 against Houston. He had two picks in that game. Asomugha has since been released.
According to Pro Football Focus, opposing quarterbacks have a 71.1 QB rating when throwing in Brock's direction, completing 21 of 38 targets for 330 yards and three scores. His four interceptions tie him for fourth in the NFL.
When the team plays the Washington Redskins on "Monday Night Football" this week, Brock will likely the second of his career. Incumbent starter Tarell Brown left Sunday's loss in New Orleans early with an apparent rib injury and will likely miss Monday's game.
Brock, 25, was originally slated to become a free agent following the season, as is Brown. Because of technicality in his contract, Brown missed out on a $2 million workout bonus recently because he missed a portion of the team's offseason program last spring.
Although he is still under contract, Carlos Rogers' future with the team is also uncertain. The 32-year-old has two years and $13.5 million remaining on his current contract and would likely have to renegotiate his deal should he remain a 49er beyond 2013.
Eric Wright received his first playing time with the 49ers last week and could be auditioning for a return next year. He is playing under a one-year, $522,648 deal. His role will be the nickel corner with Brown out and Brock taking his spot among the starters.
With Friday's signing, Brock joins Culliver as the only corner with a certain future with the team in 2014.
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