Here are some key matchups to watch:

Washington OLBs Trent Murphy and Ryan Kerrigan vs. Philadelphia RT Halapoulivaati Vaitai

The Eagles learned this week that the NFL has suspended starting right tackle Lane Johnson for 10 games for violating its performance-enhancing-drugs policy. That thrusts the rookie Vaitai, a fifth-round pick out of TCU, into the starting lineup. He’ll face the task of fending off Murphy, who has a team-high 4 1/2 sacks, and Kerrigan. The two will rotate with each other and try to overwhelm the rookie offensive lineman so that they can batter his rookie quarterback, Carson Wentz, early and often.

Washington RG Brandon Scherff vs. Philadelphia LT Fletcher Cox

Cox, who leads the Eagles with four sacks and a forced fumble, ranks among the most dominant defensive linemen in the league. Scherff will have to play at a high level to keep him at bay. Washington found it hard to run at Baltimore last week, and the challenge only intensifies this week against the Eagles, who boast one of the best run defenses in the league. Philadelphia limits opponents to 73.3 yards per game — the third fewest in the NFL.

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Washington CB Josh Norman vs. Philadelphia WR Jordan Matthews

Matthews is by far Wentz’s favorite target. Accordingly, he leads the Eagles in the receiving department, having posted 19 catches for 269 yards and two touchdowns, as well as a team-high 13 first downs. Matthews didn’t have much success against Josh Norman in their meeting at Carolina last season, managing just three catches for 14 yards. But he could have a tough time as he goes up against Norman, who ranks third in the NFL with eight pass breakups.

Washington WR DeSean Jackson vs. Philadelphia CB Nolan Carroll II

Look for a highly motivated Jackson against the former Terp Carroll; he’s champing at the bit to make a bigger impact after two quiet weeks. Although he says the extra motivation to beat his former team has worn off, and that this is “just another great opportunity to go out and try to win a game,” Jackson does badly want to get the victory and play a large role in that outcome. He doesn’t want one or two catches, he says, but 10. We’ll see whether Jackson and quarterback Kirk Cousins can manage to get in sync after the receiver has gone either overlooked for long stretches or overthrown by Cousins on the few deep-ball opportunities he has received this season.

Washington ILB Mason Foster vs. Philadelphia RB Darren Sproles

Although he’s now 33 and in his 12th season, Sproles remains an effective weapon both as a runner and pass-catcher. He is averaging 4.0 yards per carry and 13.1 yards per reception, with 165 of his 183 receiving yards coming after the catch. Foster, meanwhile, ranks second on the team with 41 total tackles and has a team-high 28 solo tackles. But opponents have found success on the underneath pass to running backs and tight ends, a space in which Sproles is sure to operate. Foster and fellow inside linebacker Will Compton will have to do a better job of reading and react more quickly to prevent Sproles from exploding for a big day.

Washington TE Vernon Davis vs. Philadelphia S Rodney McLeod

The Redskins could have to play without their top offensive weapon, tight end Jordan Reed. That means a bigger opportunity and responsibility for Davis, who this season has 10 catches for 94 yards while serving as the No. 2 tight end. He could draw coverage from McLeod, who leads the Eagles with two interceptions and 33 tackles. Cousins loves going to his tight ends, particularly on third downs, and the aging Davis still has good speed and can get open.

Washington QB Kirk Cousins vs. Philadelphia QB Carson Wentz

These two, of course, won’t face off against each other, but they’re certain to be measured against one another regardless. Each have completed 67.2 percent of their passes and thrown for seven touchdowns, while Cousins is averaging 280 passing yards per game to Wentz’s 245. Yet Cousins has five interceptions on the season to Wentz’s one, and because of that, Wentz has the better quarterback rating (103.5 to 91.1). Ball security and third downs could serve as the two big difference-making indicators on which quarterback has the better stuff on the day. Washington has succeeded on only 37.9 percent of its third-down attempts, and Philadelphia’s offense has struggled even more, converting only 33.3 percent for firsts.

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