The Buffalo Bills may have suffered a very costly win on Friday night in Cleveland.

The face of the Buffalo Bills' defense injured his knee in the second quarter, but it remains unclear how significant the injury is. Kyle Williams was seen leaving the stadium in a knee brace. Tests will determine if the ACL is torn. If it isn't, that would likely mean far less time on the sidelines.

NFL.com reports quarterback A.J. McCarron did in fact suffer a hairline fracture to his collarbone. McCarron was one of three QBs fighting for Buffalo's starting spot. No official timeline for his absence is known immediately, but it'll be at least a few weeks - meaning the Bills will have either rookie Josh Allen or Nathan Peterman under center when the open the season in Baltimore on September 9.

The Bills won by a 19-17 final, with both Allen and Peterman completing touchdown passes.