Cleveland Browns cornerback E.J. Gaines sustained a right knee sprain and will be evaluated on a week-to-week basis, the team announced Monday.
While the Browns were not specific, NFL Network Insider Ian Rapoport reported that it's an MCL sprain and that Gaines likely will be out three to four weeks.
Gaines, who signed with the Browns in March, crumpled to the ground after suffering the injury during Sunday's practice. The 26-year-old was carted off the field by the team's medical staff.
"He was a contributing member back there. He was going to play and was slated to play. That is a part of the game, we don't want to see it," coach Hue Jackson said, per the team's website. "It's football. I hate to lose him, but at the same time, we know that those things do happen."
Gaines is part of a revamped defensive secondary that includes rookie cornerback Denzel Ward, veterans T.J. Carrie and Terrance Mitchell.
The fifth-year veteran was a sixth-round pick of the then-St. Louis Rams in 2014 and missed the entire 2015 season with a Lisfranc injury. While with the Rams, he played under current Browns defensive coordinator Gregg Williams.
Gaines was traded to Buffalo as part of the Sammy Watkins deal last year and made 11 starts for the Bills. He had 59 tackles, an interception and three forced fumbles in those games.
Cleveland met with veteran free agent Bashaud Breeland recently and he remains available after meeting with several other teams.