BEREA, Ohio — Browns starting nickel back K'Waun Williams sustained his third concussion in less than a year and will sit out Sunday against Oakland, forcing changes to Cleveland's secondary.
Coach Mike Pettine said following practice Friday that Williams, who signed with the Browns as an undrafted free agent last year, complained of headaches Thursday and the team placed him in the NFL's concussion protocol. The Browns don't know when Williams suffered his head injury. He practiced the past two days and was not listed on the injury report earlier this week.
Williams also suffered a concussion on Oct. 12 last season against Pittsburgh and in the Dec. 28 finale at Baltimore.
With Williams out, right cornerback Tramon Williams will likely move into the slot when the Raiders line up three wide receivers and Pierre Desir will play outside. Backup free safety Jordan Poyer has also spent some time in the nickel position.
The loss of Williams could be costly for the Browns, who will have to handle Oakland receivers Michael Crabtree and Amari Cooper, both of whom had more than 100 yards receiving last week in a win over Baltimore. Raiders quarterback Derek Carr passed for a career-high 351 yards in the win.
Pro Bowl cornerback Joe Haden said Williams will be tough to replace.
"He means a lot to the secondary," Haden said. "K'Waun's a guy that was undrafted, so he works super-hard. He goes out there, goes hard, knows his assignment, alignment, and he locks up the slot guys. That's his thing."
Haden is also concerned about Williams' long-term health.
"Definitely, man, because that's your head," Haden said. "And K'Waun, he's a young dude. He hasn't been in the league that long, so if he's messed up like that, he felt like he needed to go get himself checked out and make sure everything's OK."
Gilbert missed Cleveland's first two games with a hip flexor and the former first-round pick, a major disappointment so far, hurt his hamstring in Thursday's practice.
Bryant didn't practice at all, and if he can't go, rookie Xavier Cooper will be active for the first time.