PITTSFORD -- After a day off, the Buffalo Bills returned to practice at training camp Tuesday, but LeSean McCoy was not on the field.
Coach Sean McDermott said before the session at St. John Fisher College that the running back developed "a bug overnight."
"We're going to continue to evaluate that and monitor his situation," McDermott said.
Meanwhile, defensive tackle Marcell Dareus, who missed practice Saturday and Sunday with what the coach called a "tweaked hamstring," was back in action Tuesday, McDermott said.
Center Eric Wood and linebacker Lorenzo Alexander each sat out practice for what McDermott described as a "veteran day off," the same reason tight end Charles Clay sat out Sunday's session.
The coach said cornerback Ronald Darby, who practiced on a limited basis Sunday after suffering an ankle injury Saturday, was back to full speed.