Buffalo Bills quarterback AJ McCarron suffered a hairline fracture of the collarbone during a preseason game against the Cleveland Browns on Friday night, the Buffalo News reported.
McCarron, Nathan Peterman and Josh Allen are competing to become the Bills' starting quarterback.
Buffalo traded its starting quarterback of the past three seasons, Tyrod Taylor, to the Cleveland Browns on March 10, signed McCarron as a free agent on March 14 and selected Allen with the seventh choice in the NFL Draft on April 26.
McCarron got the starting assignment in the Bills' second preseason game of 2018 against the Browns at First Energy Stadium in Cleveland.