McCoy injured his left ankle on a sack early in the third quarter. He stayed in the game and finished 17 of 28 passing for 241 yards, with a touchdown and an interception. He said X-rays afterward were negative, but he will have more tests Monday in Cleveland.
"I wasn't going to come out of the game," McCoy said. "We evaluated it and it hurt, but it wasn't something that I was going to pull myself out of the game over. I felt like I could still do the things I needed to do. It was bothering me, but I needed to be out there."
McCoy was sacked a season-high six times. Jeremy Mincey got him twice, with the first one doing most of the damage. Coach Eric Mangini even got backup Seneca Wallace warming up on the sideline, but stuck with the rookie who has played well since taking over for starter Jake Delhomme.
Delhomme and Wallace also sprained ankles earlier this season, injuries that led to McCoy taking over the starting job.
"It definitely bothered him and I talked to him throughout the course of the game," Mangini said. "And at one point I had Seneca warm up. [But] he felt like he could continue on."
McCoy scrambled for an 18-yard gain in the fourth, got pushed out of bounds by Don Carey and gingerly jogged back to the huddle.
Mincey sacked McCoy again three plays later, forcing the Browns to settle for a field goal and a 20-17 lead with 2:51 remaining.
It was another wasted chance for the Browns, who scored just 10 points off Jacksonville's six turnovers.
"Offensively, we didn't execute when we had short fields," McCoy said. "You've got to score more than 10 points off six turnovers. That's on us, as an offense and on me for maybe getting us to different plays ... I don't know. We're going to have to go back and look at it.
"If you want to take anything positive out of this, we fought up to the very end. Just because things weren't going well for us, we didn't hang our heads. We kept fighting and trying, down to the very last play."
Cleveland, coming off a loss to the New York Jets in overtime, had a final chance to win in Jacksonville. But Sean Considine tipped McCoy's pass away from Ben Watson at the goal line with a few seconds remaining.
The ball bounced off Watson's chest and landed in Considine's arms.
"They dropped everybody back," McCoy said. "You can't throw short routes because we have no timeouts. You've got to take a shot like that. It's risky."