“He hasn’t had a lot of work with Kirk [Cousins] as far as cadence, rhythm of the game, protections, all that stuff,” Coach Jay Gruden said of Clemmings. (John McDonnell / The Washington Post)

Here are the top takeaways coming out of Thursday’s practice and locker room availability at Redskins Park:

1) Clemmings works with the first team: Just six games into his tenure with the Redskins, offensive tackle T.J. Clemmings could be thrusted into a starting role Sunday against the San Francisco 49ers. He’s in line to fill in at left tackle if Trent Williams, who is dealing with a meniscus injury in his right knee, can’t suit up.

Williams did not participate Thursday for the second straight day, although Redskins Coach Jay Gruden didn’t rule out the possibility of Williams playing through the injury. If Williams doesn’t play, then Washington would turn to Clemmings, who has practiced with the starters this week.

“He hasn’t had a lot of work with Kirk [Cousins] as far as cadence, rhythm of the game, protections, all that stuff,” Gruden said. “This is new to him. He just got here a few weeks ago, so it’s really good to get him schooled with Ty Nsekhe being out also. We have to get him up to speed, and it’s been a great couple days for him. He’s doing a much better job.

Acquired off waivers after he was cut by the Vikings following the preseason, Clemmings spent the first four weeks as the team’s fourth offensive tackle on the active roster. Similar to his two years in Minnesota, the 25-year-old has climbed up the depth chart because of injuries. Nsekhe has been sidelined with a core muscle injury he suffered in Week 3 against the Oakland Raiders, which made Clemmings the backup swing tackle.

Once Williams went down two weeks ago against the Kansas City Chiefs, Clemmings filled in for six snaps to replace him. Clemmings, drafted in the fourth round in 2015, went through a similar situation in Minnesota. After Phil Loadholt tore his left Achilles’ tendon during the preseason, Clemmings started all 16 games his rookie season. He started another 14 games last year, but struggled rotating in at both tackle positions.

Clemmings said he learned that he has to be ready as much as possible because he can go from the sideline to the field at any given moment.

“I gained that experience of being in a game at right tackle and at left tackle in Minnesota,” Clemmings said. “So if I’m needed, I’ve got that experience to lean on. I’ve been in a game. I know what it’s like. So now, it’s just preparation throughout the week, continuing preparing like I have been and listening to what I’m being coached to do and getting tips and nuggets from the [veterans].”

2) Redskins could dress three safeties: Deshazor Everett was sidelined for the second straight day because of a hamstring injury he suffered against the Chiefs. If he’s unable to play, Washington has two options.

It could either promote rookie Fish Smithson from the practice squad as its fourth safety, meaning Washington would need to make a corresponding move to create space on the active roster. Or the Redskins could stick to their three safeties – D.J. Swearinger, Montae Nicholson and Stefan McClure – and use nickel cornerback Kendall Fuller as their emergency fourth safety. In this scenario, Josh Holsey, a seventh-round pick out of Auburn, would slide into one of the cornerback spots. Holsey is expected to be active for his first career NFL game after earning a spot on the 53-man roster with an impressive offseason.

“Kendall has been schooled a little bit at safety,” Gruden said. “[Josh] Holsey would probably be up, and he can play, obviously, nickel and corner, so the fourth safety would probably be Kendall if we needed to.”

3) Brown returns, Nsekhe progressing: Washington received good injury news with the return of inside linebacker Zach Brown at practice. He missed Wednesday because of an illness, but Gruden said Brown was “in good shape.”

Nsekhe is recovering from surgery to repair a core muscle, and he’s going to be reevaluated by a core specialist to see if he’s still on schedule in recovery. Gruden said there’s a chance Nsekhe could participate in walk-throughs next week as he eases back onto the practice field.

Nsekhe was initially expected to miss three to six weeks. Gruden said it’s possible Nsekhe could return next week against the Philadelphia Eagles, three weeks after the injury, but the team won’t rush him back.

“Probably I would say we’re hopeful for Philly but probably the following week, probably be safe; hopefully,” Gruden said.

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