Green Bay Packers offensive lineman Don Barclay suffered a torn anterior cruciate ligament during Tuesday afternoon's practice at Nitschke Field, according to a league source.
Barclay, the team's swing tackle, was carted off the practice field after falling awkwardly on his right knee. After starting all 14 games at right tackle for the Packers last season in place of an injured Bryan Bulaga, he was positioned to be the primary backup at both guard spots and right tackle.
Packers coach Mike McCarthy was standing in front of the play and said he could see him being in a "compromised position."
"Donny, they don't come any better than him," McCarthy said. "He's exactly what you're looking for. If you want someone to emulate as a Green Bay Packer football players on and off the field, he's definitely one of your guys."
Barclay's loss is a significant one for the offensive line. Former first-round pick Derek Sherrod likely will become the swing tackle at both spots with second-year guard Lane Taylor moving as the primary backup to veterans Josh Sitton and T.J. Lang.
"He adds a ton of value to this line," said Sitton of Barclay. "You typically don't get a sixth guy that can play that many positions and has had that much experience with 20 games or started. That will be a big one if he's down."
Barclay was one of four undrafted free agents to make the Packers' roster in 2012 and finished the season as the team's starting right tackle when Bulaga succumbed to a season-ending hip injury. He beat out Marshall Newhouse for the starting job in camp last season when Bulaga was lost for the season with a torn ACL.
"He's doing a lot of good things for us," Lang said. "He's a guy who has been competing all year and he's a guy who can play multiple positions and play them well."
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