Progress is in the eye of the beholder for the Buffalo Bills, who held their first practice in pads on Tuesday before veterans for any of the other 31 NFL teams have even reported to training camp.

Head coach Doug Marrone kept a sharp eye on the offense, which appeared sloppy as second-year quarterback EJ Marrone worked on his chemistry with an equally young receiving corps.

"They finished strong, but it was not what we wanted," Marrone acknowledged of the offense. "I want them to perform better, no doubt about it."

Manuel continues to work on his decision making, along with his timing with his receivers. While Marrone wasn't pleased with the overall execution of the offense, Manuel thought it was a productive practice.

"It's never just what you see. You always have to have a basis," said Manuel. "We're a progression-based offense and you always are going to go through your progressions someway, somehow. So if nobody is open, do a realistic thing, throw it away or take off and run."

Manuel is also working with several new pieces on offense. The biggest absence is that of left tackle Cordy Glenn, who is out with an undisclosed illness and replaced by rookie seventh-round pick Seantrel Henderson.

"I think in time Cordy will be fine and be healthy," said Manuel, without providing specifics on the illness. "I know he is going to work hard to get back healthy and get out there for us. The other four guys who are starters from last year, I know they're going to do great. If Cordy can't go, I'm sure one of the other young guys will come in and play a huge role for us."

There is also the issue of getting on the same page with rookie wide receiver Sammy Watkins and working running backs Bryce Brown and Anthony Dixon into a deep backfield that already includes C.J. Spiller and Fred Jackson.

With teams unable to hit during practice over the final few weeks of the regular season or at all during the offseason program, Marrone is happy the Bills opened up training camp four days before the rest of the league, don the pads and get some contact work in.

"We're not even close to where we'd like to be and we have got plenty of work ahead of us," he said.

--DT Marcel Dareus was expected to report to training camp Tuesday after having his flight to Buffalo on Monday cancelled due to weather. Dareus, granted a leave from the team after failing a conditioning test, entered a pre-trial program in Alabama in an effort to have felony drug charges dismissed. Dareus endured a tumultuous offseason that included numerous traffic violations following an alleged race against teammate Jerry Hughes on May 30. Dareus is currently on the active/non-football injury list and could face a suspension from the league.

--Second-year QB Jeff Tuel took reps with the second team offense Tuesday, and Marrone said he is in an open battle with Thad Lewis for the backup job to Manuel.

--PK Dustin Hopkins is not competing for the field-goal kicker job against Dan Carpenter and will need to earn a roster spot as a kickoff specialist, according to Marrone.