PITTSFORD, N.Y. (AP) -- Bills general manager Doug Whaley's patience is growing thin after starting defensive tackle Marcell Dareus experienced his latest offseason setback by failing a pre-training camp conditioning test.
''It's cause for concern,'' Whaley told The Associated Press after the Bills held their first practice - minus Dareus - in suburban Rochester on Sunday night.
''You always are disappointed when one of your guys isn't ready. But we think he's not far off. So hopefully sooner than later.''
Whaley then expressed confidence in Dareus, whose string of troubles include drug possession and reckless driving charges in two separate arrests in May.
''His mindset's better once he's here,'' Whaley said, referring to the practice field. ''And I think we'll find out with his actions. And I think he's ready to disprove all this stuff that he's a bad seed.''
The Bills placed Dareus on the active/non-football injury list on Saturday because the 2011 first-round draft pick did not report to camp in shape, coach Doug Marrone announced shortly before the start of practice Sunday.
Marrone declined to say whether he was disappointed in Dareus' latest setback.
''I just think right now he just needs to focus on getting himself ready, getting on the field, and focusing on football,'' Marrone said. ''And I think that's what he'll be ready to do.''
Dareus was not present for practice and has not been spotted at the team's training camp facility since players began reporting on Friday.
Under the observation of trainers, he must now work himself back into shape, and then pass the tests to be cleared for practice.
This isn't a good start for a player who has encountered a series of on- and off-field problems over the past seven months.
In early May, Dareus was arrested in his native Alabama and charged with possession of synthetic marijuana and drug paraphernalia.
Four weeks later, he was allegedly racing teammate Jerry Hughes when he crashed his 2012 Jaguar into a tree near a busy intersection not far from Ralph Wilson Stadium.
Dareus was charged with reckless endangerment and ticketed for several traffic violations, including drag racing.
The NFL could potentially discipline Dareus for his off-field troubles with a fine or suspension.
After the crash, Dareus consulted with Marrone and decided to take two weeks off from voluntary practices. He returned for the team's three-day mandatory minicamp in mid-June, but did not speak to reporters.
Dareus' troubles date to the end of last season when he was benched for parts of the final two games for breaking team rules.
Marrone had previously taken responsibility for mentoring Dareus.
''I just want to make sure that I'm clear that everyone understands that I believe in Marcell, and I will do everything I can to make sure that we can get him on the right track,'' Marrone said in June. ''I'm going to do everything I can to help a 24-year-old man make better decisions.''
And yet, it's unclear whether the player is listening.
Even Dareus' teammates have publicly expressed concerns over his poor decision-making. Veteran defensive tackle Kyle Williams, last month, said he hoped the car crash was a wake-up call for Dareus.
''Hopefully, it's to a point where it's kind of an epiphany, and he comes alive and turns the corner and does his best,'' Williams said then.
NOTES: LT Cordy Glenn, who is on the active/non-football illness list, watched from the sideline. DT Alan Branch, also on the illness list, did conditioning drills on the sideline. ... LT Seantrel Henderson did not return after being escorted to the locker room an hour into practice. WR Marquise Goodwin also did not return after being escorted off. The Bills had no updates on the players' status.
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