ORCHARD PARK, N.Y. (AP) -- Raising his right leg for emphasis, Bills quarterback EJ Manuel declared both knees to be fine, and his mind feeling refreshed.
The next step is showing how capable Manuel is in shedding the injuries and inconsistencies that limited the first-round draft pick's development during his rookie season last year.
''I definitely agree there's a lot out there for myself as a quarterback to get better,'' he said, after joining his teammates for the start of Buffalo's offseason voluntary conditioning program on Tuesday. ''I had some success. And I had some bad games as well. It's obvious.''
Manuel wasn't kidding, and the bluntness he provided in assessing his up-and-down season was a departure from a player who had become defensive in the face of criticism last year.
With a season behind him, Manuel has a new perspective for the job and feels better prepared to work on what he needs to improve upon.
''I'm eager about it. I'm excited,'' he said. ''I know there is a lot of area for me to grow. That's why I took these last four months to allow that growth.''
The first step was getting healthy after being sidelined three times because of knee issues. Manuel missed two preseason games after hurting his left knee. He sat out four regular-season games in October with a sprained right knee, and then missed the final two games after re-injuring his left knee.
''I feel fine. I feel normal,'' Manuel said, adding there were no limitations placed on him during Tuesday's workout. ''I'm very eager to play a full 16-game regular season.''
Manuel went 4-6, completed just 58.8 percent of his attempts and finished with 11 touchdowns and nine interceptions. The Bills went 6-10 to extend the NFL's longest playoff drought to 14 seasons.
Manuel's performance - and missed playing time - didn't reflect the type of production the Bills were counting on a year ago, when they used the No. 16 pick to make the Florida product the first quarterback taken in the draft.
Coach Doug Marrone maintains his trust in Manuel's potential, and expects him to continue developing.
''I think it's like all the other players. Everyone has inconsistencies in what they do, and they can work on it,'' Marrone said. ''We have EJ who has experience coming back. ... Granted it's not a lot of experience, but at least we've seen him in those situations, and that's what gets us excited.''
Manuel barely took any time off this offseason once his left knee was fully healed following a minor procedure.
He spent time in both California and Miami working out and throwing passes to teammates. The objective was to build further chemistry with his receivers, and also continue evolving as a team leader.
Running back C.J. Spiller was impressed with what he saw from Manuel during their workouts in California.
''You could definitely tell he was ready to take that next step in becoming a leader,'' Spiller said. ''Injuries played a big part in lessening his development, but he is past that now and ready to get back to work.''
The Bills are back following an eventful offseason that included owner and founder Ralph Wilson's death last month.
On the roster front, the Bills lost three-time Pro Bowl safety Jairus Byrd in free agency. Buffalo also made a few additions by signing run-stuffing linebacker Brandon Spikes to a one-year deal and acquiring Buffalo-born receiver Mike Williams in a trade with Tampa Bay.
Spikes has provided the Bills an outspoken voice, particularly when it comes to discussing the falling out he had after spending his first four seasons in New England. Spikes has engaged Patriots fans on his Twitter account, and gone so far as to vow the Bills will beat their AFC East rivals both times this upcoming season.
''What did you expect me to say?'' Spikes said. ''I ain't going to say, 'I hope the Patriots beat us.' Like, come on. I said some things. It was in the past. I meant it and it's over with. I'm ready to move on.''
NOTES: Marrone said about 90 percent of the Bills 75 players attended the first day of the voluntary session. ... The Bills re-signed three exclusive-rights free agents: WR Chris Hogan, OL Antoine McClain and FB Frank Summers.
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