However, coach Rex Ryan loves his cornerback's response.
''You throw him to the wolves and that's no easy thing,'' Ryan said. ''He did get a little baptism by fire and things, but I like the way the kid's responded.''
Darby started with the first unit because of an injury to Leodis McKelvin, and he was picked on by Carolina in the 25-24 loss.
The second-round pick out of Florida State was late turning around in being beaten on Kelvin Benjamin's TD catch. Darby had solid coverage on Ginn's 38-yard catch, but was beaten by Cam Newton's perfectly placed pass.
''First game as an NFL pro,'' Darby said. ''Just adjusting to the game speed, tempo, understanding things. First piece is the game, got it under my belt, so I'm just going to continue to get better each week.''
Darby knew it wouldn't be easy to adjust to the NFL, but says his confidence is far from fragile after his spotty start. And his teammates have been impressed by the rookie.
''Very grounded, takes care of business off the field and that's all you can ask for,'' Bills wide receiver Marquise Goodwin said. ''As long as he gives his best when he's out there, he'll get better each day.''
Darby will have another new experience Monday, when Buffalo will host the Cleveland Browns for two days of combined practices before Thursday night's preseason game in Ohio.
The game reunites Ryan with his good friend, former Jets defensive coordinator Mike Pettine, who's now the head coach of the Browns.
Pettine left New York to take the same position with the Bills last season, and Ryan understands his friend's decision.
''It was a lateral move and a lot of guys left, didn't they?'' Ryan before adding, ''I wonder why that is. Any time you've got a new GM, it's like `Get out'.''
Ryan is ready for the pair of practices, and Pettine has said they won't be a ''pillow fight'', and Browns linebacker Karlos Dansby promised ''fireworks''.
''We'll conduct business if business is being done to us, but you don't want a pillow fight,'' Ryan said. ''You want to compete. It should be a higher intensity level when you're going against an opponent.''
And Ryan's going against a kindred spirit in Pettine.
''We're very similar,'' Ryan said. ''Even to the same slogans and things we picked up that we all believed in.''
Buffalo is dealing with injuries after Friday's loss. Ryan said defensive tackle Jarius Wynn might be lost for the season after a ''serious'' ACL injury, and called the injury `'devastating'' to both the Bills and Wynn.
Buffalo added kicker Dan Carpenter to the active roster, moving him off the active/non-football injury list.
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