Redskins running back Adrian Peterson (26) leads the NFL in rushing yards after contact. (John McDonnell/The Washington Post)

Through three games, the Washington Redskins rank fourth in the NFL in total rushing yards with 413. That is an impressive stat, especially given the struggles the team had on the ground a season ago, and a promising development as the team enters its bye week with a 2-1 record, which has it tied for first place in the NFC East with the Philadelphia Eagles.

Is the growth they’ve achieved in this area sustainable for the rest of the season? Let’s take a look at four key factors: the performance of the running backs, the run-blocking of the offensive line, the mobility of quarterback Alex Smith, and the play-calling and schemes of Coach Jay Gruden.

Adrian Peterson has been a revelation. The 33-year old back has had two very strong games to start the season and 236 total rushing yards — good enough for fifth in the league, just behind Rams star Todd Gurley. Even more impressive, though, is that Peterson leads the league in yards after contact (175) and has broken 11 tackles on running plays, tied for third-most in the NFL.

Chris Thompson hasn’t been as prolific, with a role more heavily involved in the passing game, but he has been effective when he has carried the ball. A lot of the hard work is being done by these two running backs, as opposed to the team’s offensive line.

The Redskins have graded poorly in run-blocking. This is something of a surprise, given the track record of several of the team’s offensive linemen, but the line has struggled to open holes in the running game. Only left tackle Trent Williams has earned an above-average run-blocking grade from Pro Football Focus through three games.

Brandon Scherff and Morgan Moses have been good run-blockers in the past, but both have been below-average this season. Even if the team isn’t able to get high-level performances from all five starting linemen, an improvement on the parts of Scherff and Moses should provide even more promise for the team’s running game.

Alex Smith has had a positive impact. Smith has 48 rushing yards to his name, which is more than 10 percent of the team’s total on the ground. If you take out three kneel downs that count as rushing attempts, he has had three designed runs on options, two quarterback sneaks and taken off 10 times on passing plays to scramble for yardage.

Those scrambling plays are worth noting simply because of the inflating effect they have on the raw rushing totals, but it’s the option plays that are interesting when it comes to how Washington is scheming to assist the run game.

Washington has deployed a read-option look with Smith 16 times this season, which is tied for the fourth-most in the league. Carolina is way out in front with 33 such plays, but no other team is above 20. In theory, defenses should always respect the threat of the quarterback running in the read-option game, but we have seen in the past that this look is at its most effective when the quarterback is actually a viable threat to exploit it. Smith is athletic enough to do so, and that creates some more space inside for the running backs, even without Smith keeping it himself very often.

The play-calling and schematic wrinkles have been effective. With the line not playing at its usual level, the credit for the team’s success in the ground game goes not just to Smith and the running backs, but the diversity in the team’s schemes.

Some teams rely on just a couple of different broad run concepts all season, varying only the plays within those broad buckets, but the Redskins have mixed it up. They have deployed inside-zone, outside-zone, duo and power-run concepts each on more than 15 percent of their attempts and counter plays on another 9 percent, meaning defenses can’t simply dial into defending one or two specific blocking concepts.

They also have effectively employed run-pass option plays, or RPOs. Smith ran these a lot last season with the Kansas City Chiefs, and they effectively fold in multiple options on one play, putting the defense in an difficult situation in which it is caught in a wrong alignment no matter how it chooses to defend. Since the start of the 2017 season, running RPOs have averaged 4.4 yards per carry, compared to just 4.0 yards per carry on rush attempts that did not have an RPO element, and that’s not even factoring in the free yardage these plays manufacture in the passing game.

This season, Washington has averaged 4.7 yards per carry on RPO plays, a tick better than their non-RPO carries. The Redskins have run RPO plays 23 times this season, fourth in the league behind only the Chiefs, Eagles and Bears.

The fact that so much of the running game success has been the result of the team’s running backs and play-calling can lead to one of two conclusions: 1. The success is unsustainable and that the poor run-blocking will catch up to the Redskins; or 2. The potential for the run-blocking to return to its normal level, when combined with elusive running backs, a mobile QB and smart coaching, means this could be one of the better ground games in the NFL this season.

The track records of players like Williams, Scherff and Moses seems to point toward the latter, even if Peterson can’t maintain his hot start all season long. If they do, defenses are going to have a tough time combating Washington’s rushing offense in the weeks to come.

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