After the game, which the Lions won 23-0, Bills coach Doug Marrone deferred comment on Watkins to a team spokesperson, who said he was "not aware" of any test results on Watkins' ribs.
"It was a tight throw. He just probably got a little banged up," quarterback EJ Manuel said. "He'll be fine."
Marrone decided to play Watkins in the finale to give the rookie more playing time with Manuel.
"Once the trainers cleared him to play, I was excited about it," Marrone said. "He hasn't really played since the first quarter of Pittsburgh. And he really didn't play before that because we were planning on playing him a lot in the Tampa game.
"So he hasn't really played that much. I always get concerned when people come out. I think, especially when you're a rookie, you gotta play. You just don't want to throw him in there during the season. So we're behind on that."
Marrone reiterated his stance that recovery from rib injuries can be uneven.
"You never know. X-rays, tests, things like that. Shows up one day, doesn't show up the next day. Could be out, could be in. Depends on the player," he said. "Could be a week, could be four to six weeks, could be longer. I'm not getting into all of that."