Eagles Andre Dillard trying to get it right on the other side of the offensive line

For the second time this season, Andre Dillard is preparing to replace an All-Pro tackle with a pivotal game on the horizon.

Except there is no replacing Lane Johnson, just like there’s no replacing Jason Peters.

Johnson left the Eagles’ loss to the New England Patriots on Sunday with a concussion, and he took the team’s offensive production with him. The team went scoreless after the seven-year veteran went to the locker room. Johnson was still in the concussion protocol on Thursday and has yet to be cleared to return. Preparing for the worst, the Eagles have Dillard practicing at right tackle, where he will start if Johnson can’t play.

Dillard was the Eagles’ starting left tackle for three straight weeks, as Peters, 37, recovered from a knee injury that required arthroscopic surgery. The rookie’s first start came against the Dallas Cowboys in Week 7. The first-round pick out of Washington State played well in Peters’ absence, but he still was relegated to the bench once the 16-year veteran returned against the Patriots.

Being the heir apparent to Peters, a nine-time Pro Bowler and two-time All-Pro, Dillard has spent most of his time with the Eagles on the quarterback’s blind side. He got some reps as a right tackle during training camp and played there sparingly in the preseason.

When Johnson left in the second quarter of the Eagles’ 17-10 loss to the Patriots, Halapoulivaati Vaitai came in for the 2017 All-Pro tackle. Coach Doug Pederson said this week that the team didn’t want to throw Dillard into an unfamiliar situation in that game but would get him ready to play on the right side in practice.

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What challenges will the 24-year-old face in his transition?

“His head’s a little more to the right,” Pederson said, joking. “One of the things we loved about Andre is not only his durability but his flexibility, his versatility to play both left and right [tackle]. And, even though he’s been limited on the right side — he’s primarily a left tackle for us — this will be a great week of preparation for him to really kind of hone his skill and be a swing tackle in that case.”

Pederson added that movement patterns are completely flipped when swinging to the other side. Even little details such as which hand goes down in a three-point stance are changed.

Eagles’ offensive coordinator Mike Groh said many offensive linemen make it look simple, but it’s far from it.

“Changing up your stance and which hand is on the ground and your footwork and all of those kinds of things,” Groh said. “It probably seems easy, but not necessarily as easy as a lot of guys make it look.”

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Brandon Brooks, who switched sides with the Houston Texans for one game in 2015, echoed Groh’s sentiment that swingers are underappreciated.

“It’s a lot harder than what people think,” Brooks said. “Not only are you flipping all the plays to completely opposite, but the muscle memory, your stance, is a little bit different.”

Dillard has proven to be up for the challenges the Eagles have thrown him. He’s played significant snaps in four games and has been used as a tight end on some of the overload formations, when they get an extra blocker on the field for running plays.

Over the three weeks he was starting, he was ranked the No. 23 tackle in the NFL by Pro Football Focus. He committed his first penalty of the season against the Patriots, a false start lined up as a tight end, but has yet to be called for holding.

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If he ends up filling in for Johnson, he’ll be matched up with Seahawks edge rusher Jadeveon Clowney while in an unfamiliar space. Still, Brooks feels good about his new neighbor.

“I have nothing but faith in Andre Dillard,” Brooks said. “Everything he’s done. Busting his [butt] out there. All the reps. All the extra time I’ve seen him after practice and stuff. It’s different, I said it after the game, you don’t replace Lane Johnson, he’s a one-of-a-kind talent, one-of-a-kind player, but at the same time, Dillard has more-than-enough talent, and he’s capable to handle his own.”

Eagles receiver Nelson Agholor missed Thursday’s practice with a knee injury but said he is “day-to-day” and hopes to return to the field for Friday’s practice. ... Jordan Howard and Alshon Jeffery were limited Thursday. Howard is still waiting to be cleared for contact with a shoulder stinger, while Jeffery is working back from an ankle injury. Both players got hurt on Nov. 3 against the Chicago Bears. ... Safety Rudy Ford missed practice with an abdomen injury that limited him on Wednesday.