Dareus was finally back after missing the first three days of training camp in suburban Rochester. Dareus released a statement through the team, saying he hoped to regain his teammates', coaches' and fans' trust after a troubled off-season.
Dareus was arrested twice in the span of four weeks in May, and then reported to camp out of shape and failed a conditioning test Saturday.
"I have a passion for this game and I want to be here to help this organization achieve its goals," Dareus said in the statement. "There are things I need to work on professionally and personally to make sure I can be accountable to myself, my family, this team and this community."
Dareus was excused from the start of camp to attend a court hearing in his native Alabama on two felony drug charges. Dareus was arrested May 5 and charged with possession of synthetic marijuana and drug paraphernalia (a glass pipe).
On Monday, Dareus agreed to enter an NFL substance abuse program in a bid to have the charges dismissed.
The next step is getting in shape.
The 2011 first-round draft pick is on the team's active/non-football injury list and must pass a conditioning test before he can get on the field.
On Wednesday, Dareus rode a stationary bike and then spent time working on other conditioning drills while the Bills practiced.
The Bills have a day off Thursday, so Friday is the earliest Dareus might begin practicing. He has now missed four days of workouts since camp opened Sunday.
Coach Doug Marrone was pleased to have Dareus back. He wasn't sure when the player might be ready to hit the practice field.
"We're going day by day," Marrone said. "I don't want to get ahead of myself."
Even when Dareus is cleared for practice, the former Alabama star has other obstacles to overcome.
Dareus also faces a reckless driving charge after crashing his 2012 Jaguar into a tree after an alleged car race with teammate Jerry Hughes not far from Ralph Wilson Stadium on May 30.
The arrests open the possibility that the NFL will discipline Dareus with a fine or suspension.
Dareus' troubles go back to the end of last season, when he was benched for parts of the final two games for breaking team rules.
General manager Doug Whaley told The Associated Press on Sunday that Dareus' failed conditioning test was "a cause for concern" but expressed confidence the player can get his life and career back on track.
"His mindset's better once he's here," Whaley said. "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."
Dareus has been a three-year starter in Buffalo since he was drafted with the third overall pick out of Alabama. He's coming off a career season in which he was credited with 71 tackles and 7 1/2 sacks and made his first Pro Bowl appearance as an injury replacement.
Dareus wasn't available to reporters Wednesday. He hasn't made any public comments since May, before his car crash.
"I'm excited to return to training camp to rejoin my teammates in our preparations for the 2014 season," he said in the statement. "I want to thank the Bills organization, coach Marrone and the coaching staff, my teammates and our fans for their continued support."
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