After saying last week that he wasn't pleased with the competition at left guard, Buffalo Bills coach Doug Marrone added another layer to the battle on Wednesday.
Left tackle Cordy Glenn, who started 13 games as a rookie last season, was cross-trained at left guard for Wednesday's practice.
"We're not experimenting with him not being the left tackle," Marrone stressed. "We know that down the road from now, when we're dressing seven linemen, we'll have a swing inside player and a swing outside player. That's why we wanted to work him (at left guard) today."
Marrone hinted that it may have been a one-day move, although the Bills' uncertainty at left guard could eventually land Glenn back inside.
"I saw what I needed to see, meaning that he can do that and make the transition," Marrone said.
In Glenn's place, Thomas Welch took first-team reps at left tackle.
"We're looking at him as obviously competing for a starting position," Marrone said. "If you're not the starter, then you have to be able to swing."
Passing along some other news and notes from Wednesday's practice:
Quarterback Kevin Kolb was not on the practice field, two days after missing Monday's scrimmage due to a death in the family. Marrone said he anticipates Kolb arriving back to training camp on Thursday night, and that the medical staff will determine if his knee, which he injured Saturday, is healthy enough to let him practice.
Cornerback Leodis McKelvin also did not practice, after participating in Monday's scrimmage. Marrone said McKelvin was sore and the team is "trying to be smart" about his recovery from an offseason groin injury.
Marrone said that safety Mana Silva, who was placed on the exempt/left squad list Tuesday, did not inform the team before leaving camp on Monday. "He did not contact me or speak to me about the decision," Marrone said. "I'm concentrating on the guys that are here." Silva will be away from the team indefinitely, per a source. "It's been very hard to try to talk somebody into playing," Marrone said Wednesday.
To fill Silva's roster spot, the Bills signed safety Mark LeGree on Wednesday. This is LeGree's seventh NFL team after being drafted in the fifth-round by the Seattle Seahawks in 2011. The 24-year old played at Appalachian State and will wear No. 30 with Buffalo.
Safety Duke Williams, who left Saturday's practice with concussion-like symptoms, was medically cleared and back on the practice field Wednesday.
The Bills on Wednesday announced that Antwon Bailey, Michael Grant, Matthew Scott, Jamar Nesbit and Kevin Mawae were selected as the 2013 Bill Walsh Minority Coaching Fellowship participants, and will assist the coaching staff during training camp.