CLEVELAND -- Buffalo's quarterback situation is more scrambled than ever.
McCarron, who signed with Buffalo as a free agent for a chance to start after four years as a backup in Cincinnati, didn't show any obvious signs of being hurt while he was on the field. The 27-year-old was hit hard from behind by Myles Garrett and sacked by Larry Ogunjobi, but the Bills didn't disclose his injury until the fourth quarter.
"We'll know more as we get back to Buffalo tomorrow," McDermott said.
McCarron completed just 3 of 6 for 12 yards during four series, and Buffalo's offense gained only 22 yards on 12 plays while he was behind center.
The Bills have wanted to take a cautious approach with Allen, the No. 7 overall pick who has all the physical tools and may only need game experience. He's been coming on strong of late, and his latest performance may push McDermott to move him into the starting lineup.
Allen fired his 2-yard TD pass to Streater in the second quarter and led the Bills on three scoring drives. He completed 9 of 13 passes for 60 yards and was sacked once.
He was asked if he's made a case to start
"That's not up to me," he said. "That's completely up to the coaches, and obviously whatever happened tonight with AJ, it's some tough circumstances. Everybody that knows him knows that he's a great dude and I'm hurting for him tonight. I sent him a little text. You hate to see it happen.
"But as of now, I'm looking to improve. I know there's a lot of things to improve on and I'll continue to do that."
Peterman, who started two games as a rookie in 2017, was 8 of 10 for 113 yards and a score.
Allen, who was promoted to second-string earlier this week, replaced an ineffective McCarron with the Bills trailing 7-0 and led Buffalo on two scoring drives for a 10-7 halftime lead.
Allen badly misfired on his first pass attempt before settling in. Helped by a 22-yard run from Marcus Murphy, Allen took the Bills to the Cleveland 2. After two running plays were stuffed, Allen showed poise and precision with his TD pass.
Dropping back, he first avoided rushing Browns end Nate Orchard and then took several steps toward the line of scrimmage before threading his pass to Streater in the back of the end zone.
Bills wide receiver Corey Coleman was booed after making a 7-yard catch in the third quarter. The former first-round pick asked the Browns to trade him last week after two disappointing seasons.
"I think they missed me," Coleman said, smiling. "It was good to come here and come back with a victory."
Coleman was featured on the most recent episode of HBO's "Hard Knocks" and did not come off well while asking Jackson to trade him.
"They should've showed the whole thing if they were going to show some of it," he said. "I just laugh at it because it's kind of funny. I'm gonna take the high road."
Browns rookie quarterback Baker Mayfield, the No. 1 overall pick, had some nice moments in his home debut. Mayfield finished 7 of 13 for 75 yards.
"He didn't blink," Jackson said. "That's what I love about him. Baker is still contained, keeps his eyes down the field and there were a couple of times he got hit early, that's water off a duck's back to him, let's keep going."
Cleveland starting QB Tyrod Taylor didn't do much against his former team, completing 4 of 7 pass for 22 yards in four series. The Bills traded him in March to the Browns.
After gaining just 50 yards rushing on 33 carries last week, the Browns put an emphasis on their running game in practice.
The extra work paid off as Cleveland ran for 63 yards on its opening possession.
"We wanted to come out and show that we can run the ball this game," Taylor said. "It's more of an attitude and I think guys did a great job of clearing holes and allowing the running backs to go out there and do their thing.
While a giant American flag was unfurled across the field, players lined up along both sidelines for the signing of "The Star-Spangled Banner" without the slightest hint of a protest.
Bills: McCarron's injury wasn't the only major one as standout defensive tackle Kyle Williams injured his right knee in the first quarter.
One of Buffalo's leaders, the 35-year-old Williams left FirstEnergy Stadium with his leg immobilized. He didn't speak with reporters. Williams went down during a running play and as trainers ran onto the field to check on him, Taylor came over and checked on his former teammate.
Bills: Host the Cincinnati Bengals on Aug. 26.
Browns: Host Super Bowl champion Philadelphia Eagles on Aug. 23.
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