McCoy, making his pro debut, left after an interception late in the third quarter. Right tackle Casey Bender was pushed back as McCoy followed through on his pass, and McCoy left minutes later for the locker room.
"It doesn't look like it's anything too serious," Browns coach Eric Mangini said. "But, it being preseason, we wanted to err on the side of caution with anything like that. He'll be evaluated by our doctors when we get home over the next few days."
The former Texas star had been shaky to that point -- going 5 of 10 for 25 yards and two interceptions and scrambling for 25 yards after entering in the second quarter.
McCoy, Cleveland's third-round draft pick, was knocked out of last season's BCS championship game in the loss to Alabama on the Longhorns' first drive with a pinched nerve in his throwing arm.