Morgan Moses could be the only regular Redskins starter to play on the offensive line Sunday. (Mark Tenally/Associated Press)

As the Redskins scattered across three practice fields to begin individual drills Wednesday, Coach Jay Gruden watched as offensive line coach Bill Callahan instructed his linemen in their usual spot near one of the end zones.

With four of Washington’s five starting offensive linemen on a separate field rehabbing their injuries, Gruden stopped and blurted, “Who the hell are these masked men over here?”

After a wave of injuries has required an infusion of new faces, it’s a valid question. There are 12 offensive linemen on the 53-man roster, including three signed in the last week. Six of them are hurt in some degree, including all five starters.

Only one starter, right tackle Morgan Moses, practiced Wednesday, while Trent Williams, Brandon Scherff, Shawn Lauvao and Spencer Long did not participate. Washington’s offensive line has been a stable unit since 2015, but the Redskins could start their third different offensive line combination in as many weeks Sunday against the Seattle Seahawks.

“I think we have to go with the guys that are practicing right now,” Gruden said. “We have to prepare them to get ready to play. Anybody of these guys who did not participate, if they get ready, it’d be a bonus.”

Rookies Chase Roullier and Tyler Catalina made their first career starts at center and right guard against Dallas, and they would be in line to start again if Long (knees) and Scherff (knee) can’t play.

Williams will likely miss his second consecutive game because of a right knee injury, meaning T.J. Clemmings, who was claimed off waivers before the season opener, would be in line to start at left tackle if Ty Nsekhe doesn’t return from a core muscle injury that’s kept him sidelined for the last four games.

Lauvao suffered a stinger against the Cowboys that could keep him out. Arie Kouandjio, who was cut by Washington before the season and signed off the Ravens practice squad Saturday, filled in for Lauvao at left guard and will probably serve the same role if Lauvao doesn’t play.

“You go from Brandon Scherff, who is a Pro Bowl guard, and me and him have been there for three years playing together, you build that chemistry, then you go to a rookie in Catalina,” Moses said. “Being able to be a veteran guy out there, I’m able to help them and say, ‘Hey, I see this.’ You just kind of have to enhance your talking to guys and let them know because they’ve never seen those looks. Maybe for Catalina before he got in Sunday, his last snap was preseason. In preseason, they’re not really going 100 percent, so he doesn’t know, when the bullets are flying, what to do.”

Washington’s offensive line allowed four sacks and nine quarterback hits against the Cowboys. It also struggled to establish the run, gaining just 49 yards on 15 carries in rainy conditions.

Further complicating a patchwork offensive line that could feature four backups in starting roles: simply communicating at CenturyLink Field, widely known as one of the most hostile environments in the NFL. The offense will practice silent counts this week, and Gruden said that the Redskins will practice indoors Friday to prepare for the crowd noise.

“You have silent counts, you yell and scream, you can make sure the huddle is tight, you prepare for it with noise at practice and you do the best you can make sure you’re on the details,” quarterback Kirk Cousins said. “What are the challenges for the new offensive linemen? I mean, you name it. We have all kinds of code words and terms and snap counts and techniques. … It’s a lot. We’ve got to be given a crash course in trying to learn as fast as we can.”

The Seahawks have recorded 17 sacks this season, tied for 15th in the league, and they’re 20th in run defense, allowing 117.7 rushing yards per contest. Seattle’s defense is coming off a home victory against the Houston Texans in which it allowed 38 points. That was one of just two games this season in which Seattle allowed its opponent to score more than 18, however.

Despite the amount of injuries on the offensive line, and the entire offense for that matter, there could be opportunities available for the Redskins in this difficult matchup. No matter who suits up in the trenches, communication will be vital factor in the offense’s success.

“It doesn’t really matter who it is [next to you],” Roullier said. “Whoever it is, it really takes a few reps to kind of start to figure out at least where they’re going to be. If you’ve got two guys that have been playing next to each other for years, they’re going to have an almost telepathic way of communication. You’re not necessarily going to get that, but it only takes a couple of reps to figure out where the guy next to you is going to be in certain situations.”

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