The Falcons have one of the worst defenses — statistically — in the NFL, and they elected to let the trade deadline slide by without trying to upgrade.

The Falcons put a lot of faith in their fundamentals-and-developmental program, which they call Plan D.

The Falcons (3-4) will get to see if they made a prudent decision Sunday against the surprising Redskins (5-2), who made a move to add safety Ha Ha Clinton-Dix, at 1 p.m. at FedEx Field in Landover, Md.

"Anytime that you can add a Pro Bowl-type player like Ha Ha, you have to welcome him to your football team," Redskins coach Jay Gruden said.

» Michael Cunningham: Underdog Falcons remain a wild-card in Washington

The Falcons contended that they have the players “in the building” that they need to improve on defense.

Stopping Ol’ Man Peterson

Adrian Peterson, 33, is on pace to rush for 1,340 yards.

Former New York Giants running back Ottis (O.J.) Anderson rushed for 1,023 at age 32 in 1989.

The great John Riggins, a Pro Football Hall of Famer, rushed for 1,347 yards at age 34 in 1983 and 1,239 at age 35 in 1984.

Frank Gore ran for 1,025 yards at age 33 in 2016 for the 49ers. He’s still playing at age 35 for the Dolphins.

Peterson missed practice time last week with a shoulder injury.

“Facing A.P., we have to get a lot of hats to the ball,” Falcons defensive tackle Grady Jarrett said. “We have to try to put together back-to-back good weeks against the run.”

Running the ball vs. Skins 

The Falcons identified their rushing attack as one of the areas that must be improved over the bye week.

Because of injury, the Falcons will start their third combination along the offensive line, with Ben Garland taking over at right guard for Brandon Fusco.

The Falcons average 83.3 yards per game, which ranks 30th in the league. The Redskins, who held the Giants to 38 yards rushing Sunday in their 20-13 win, allow 80.1 yards per game, which ranks second in the league.

The Redskins are playing off defensive tackles Da’Ron Payne, Jonathan Allen and Matt Ioannidis.

“They have a lot of talent up front,” Falcons center Alex Mack said. “They are playing really hard. They are big, strong guys.”

» More: Falcons depth chart against Redskins

Inside linebackers Zach Brown and Mason Foster have been free to run to the ball and stop the run.

“The whole defense plays well together,” Mack said. “It’s a bad combination. That makes it difficult.”

The Falcons need to get the run game going so that teams will continue to honor their play-action fakes.

“The only way to go forward is to keep battling on,” Mack said. “They are going to be a good front that is not going to give us many yards easily. We have to try and keep chipping away and hope we get some explosive runs. …They are going to be talented, and we have to keep working.”

Three key matchups

Falcons WR Julio Jones vs. Redskins CB Josh Norman: The Falcons' passing attack runs through Jones, who has 812 yards receiving on 53 catches. When the Falcons get to the red zone, he's a decoy. Norman and Jones used to match up regularly when he played for the Panthers. "If we ask him to travel with Julio, I'm sure he'll be up to the challenge," Washington coach Jay Gruden said. "He is one of the greatest competitors that I've been around. He loves the challenge of going against the best because he considers himself one of the best. If we ask him to travel, he'll travel."

Falcons RG Ben Garland vs. Redskins DT Matt Ioannidis: While Washington defensive tackles Da'Ron Payne and Jonathan Allen have been drawing double-teams, Ioannidis has been wreaking havoc. He has 5.5 sacks on the season.

Falcons LB De'Vondre Campbell vs. Redskins TE Jordan Reed: Alex Smith is known in most fantasy leagues as the original "Checkdown Charlie." Reed is his main checkdown guy for the Redskins, as he leads the team in receptions with 29.

QB corner: Matt Ryan on the Redskins

On why the Washington defense has been so difficult for teams to move the ball: "They're big and physical in their front-seven. … (We must) play (with) good pad level up front. That's going to be critical for us to play well against a good defense."

On the safety position and D.J. Swearinger: "He's playing really well and is doing a great job of taking the ball away. Whether it's interceptions, causing fumbles, recovering fumbles. He's got a knack for getting the ball out."

On Josh Norman: "He's talented. He's a good pattern reader. He's smart, diagnosing what you're trying to run against what they do. He's always been that way throughout his career, he's had a knack for that. He has great ball skills."

About the Redskins 

» The Falcons face the streaking Washington Redskins, who have won three in a row.

» After an embarrassing 43-19 loss to the Saints, the Redskins have posted wins over Carolina, Dallas and the New York Giants. The also have victories over the Cardinals and the Packers and a loss to the Colts.

» It will be the 25th regular-season meeting between the teams. The Redskins lead the series 14-9-1. The Falcons have won the past five meetings.

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