Allen, the No. 7 overall pick out of Wyoming, was 9-of-13 for 60 yards with a scoring pass and added 18 yards on three carries. Perhaps more impressive was the impact he had on the entire offense. After starter AJ McCarron led the Bills to four consecutive three-and-outs to open the game, Allen took over and led Buffalo to points on all three of his drives — two field goals and a 2-yard touchdown pass to Rod Streater.McCarron reportedly suffered a hairline fracture of his collarbone during the outing. The Bills announced he sustained a right shoulder injury.Mayfield, the No. 1 overall pick who threw for more than 200 yards and two touchdowns in his NFL debut last week, was 7-of-13 for 75 yards with no touchdowns or interceptions on Friday. His numbers were better than starter Tyrod Taylor, who was 4-of-7 for 22 yards with no scores and no turnovers.Fellow Browns rookie Nick Chubb impressed, running for 53 yards and a score on 11 carries. Starter Carlos Hyde also played well, with nine carries for 64 yards and a touchdown.