After opening the season with a rushing attack that ranked among the top 10 in the league, and then taking a giant plunge midway through the season while injuries ravaged the running game and offensive line, the unit was in complete flux.

But in four of the last five games, Washington has had a 100-yard rusher, thanks largely to the emergence of rookies Roy Helu and Evan Royster, but also because of an offensive line that finally has started to jell after new pieces were added to the mix due to injuries (season-ending for left guard Kory Lichtensteiger and reoccurring for right tackle Jammal Brown), and the suspension of Trent Williams.

Center Will Montgomery and right guard Chris Chester have remained constants. But the Redskins have been able to run the ball despite being on their third left tackle in rookie Willie Smith, another rookie in seventh-rounder Maurice Hurt at left guard, and Tyler Polumbus filling in at right tackle until Brown returned from injury last Saturday.

In the last five games, the Redskins have averaged 128.8 rushing yards, tied for 10th-best in the league.

“We’re kind of getting back into the flow of our running game,” coach Mike Shanahan said. . . . “Over the last four or five games, we’ve had that flow and, in order to score points with the football like you want to, you have to be productive in that area.”

While encouraged by the production and improved offensive line play, Shanahan hasn’t been surprised by the late-season turnaround. Instead, the coach said the execution seen in the last few weeks was expected of those players when they received opportunities to play.

“Guys get opportunities to show us what they can do, regardless of if they are second-team or third-team,” Shanahan said. “They’re patchwork, but they play in the NFL and they’re here for a reason. They’re one play away from being the starter. If you’re third-team, two plays away from being the starter. If you’re on the team, you’re on the team for a reason and we expect you to produce. I think these guys have gained some valuable experience. Along the way, we’ve gotten better collectively. We had a little dry spell in there and I think we’re starting to come along.”