GREEN BAY – Don Barclay’s comeback from a torn ACL got a lot more challenging this week.

With David Bakhtiari sitting out practice with a sore knee, Barclay moved from right to left tackle, and for the first time on Sunday in Pittsburgh, the Pittsburgh native will be taking NFL game snaps as Aaron Rodgers’ blindside protector.

It’ll be a big moment for the versatile fourth-year pro, who until this week had practiced at each of the other four offensive line positions for the Packers.

He’ll get a chance to show not only that he’s closer to being all the way back from last year’s season-ending injury, but also that he can be the next man up at the premier position on the offensive line.

The quiet, soft-spoken 305-pounder isn’t letting the task overwhelm him, though. To the former three-year starter at left tackle for West Virginia, there’s a job to do that he’s done before, and that’s all there is to it.

“I feel like everywhere on the line, you’re going to have one-on-one battles either way, whether you’re at right tackle, left tackle,” Barclay said on Friday. “You can be the blind side at right tackle some plays if he’s looking left.

“It definitely has that name on it. I’ve played the position in the past. It’s nothing new to me. I just have to execute, bottom line.”

Barclay’s business-as-usual approach is the same one he took when he was thrust into the starting lineup as an undrafted rookie in the final month of the 2012 season with the Packers in the playoff hunt.

That became the first of his 21 career starts (including playoffs), all at right tackle, and he was slated to be the Packers’ first option off the bench at right tackle or either guard spot last year before he tore his ACL in training camp.

By all accounts his recovery has gone well, but last week in New England, his first game action since the 2013 wild-card playoff game vs. the 49ers, he was clearly rusty and did not look like the pre-injury Barclay.

To a certain extent, that was to be expected, and that’s why neither Rodgers nor offensive line coach James Campen expressed any worry this week as Barclay took all the reps at left tackle with the first-team offense.

“I think Donnie has looked really strong,” Rodgers said. “He’s a natural left tackle. I don’t think that’s a position he feels uncomfortable in.

“Like anybody playing a different position, you’re going to want to give him some help at times, but we expect him to play well. Donnie can do a lot of things for us. He can play really all five positions on the offensive line, and that makes him a very invaluable person to our team.”

Barclay appreciates the trust and the votes of confidence, which he earned his first two years in the league by coming through in tough situations. After three weeks of training camp, he said he feels “close” to being all the way back from the knee injury.

“He had some mistakes in there, he’d be the first to admit it,” Campen said of the preseason opener. “There just comes a point where you have to trust yourself, trust your technique, forget about it and go on. Don Barclay has always been that type of guy.

“He’s tough as hell. He’s mentally tough. He’ll make the wrongs right and move on real quick.”

Bakhtiari’s knee injury hasn’t been categorized as serious, and Barclay isn’t the only backup option at left tackle if a replacement were needed in the regular season.

Starting right tackle Bryan Bulaga could swing over there as well, but ideally Barclay can nail down the No. 2 spot and minimize any potential lineup shuffling down the road.

“I would hope as each series or play goes forward that he gains some experience and some knowledge in a live environment,” Campen said. “I hope that as the game goes on, however long (the starters) play, that he gets better and better each series, can see it and move forward.”

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