Washington quarterback Kirk Cousins eventually found a bit of a rhythm Saturday, but it was against Green Bay’s backups. (Photo by John McDonnell / The Washington Post) (John McDonnell/The Washington Post)

For an accomplished offense, it was an embarrassingly simple request: Just score against the backups. The Washington Redskins may have been one of only three NFL teams to average more than 400 yards per game last season, but if you needed a reminder of how little that matters now, just watch them learning to crawl again this preseason.

On Saturday, for a second straight exhibition game, quarterback Kirk Cousins and the first-team offense floundered about, causing some level of concern over how long it will take this reconstructed unit to mesh. After the 21-17 loss to the Green Bay Packers, it may be premature to develop too many grand opinions about the offense, especially with tight end Jordan Reed out and several wide receivers recovering from injury or working to gain better chemistry with Cousins. But it’s safe to assume that this small sample size speaks to a transition going on within Washington’s best unit. There is considerable change, from Coach Jay Gruden taking over play-calling to Terrelle Pryor Sr. getting acclimated, and the team has just three weeks to develop cohesion before the regular season begins.

It raises the question: What if the offense struggles early?

“We’re a work in progress,” Gruden admitted late Saturday night. “No question about that.”

In two seasons with Cousins as the starter, the trend has been that the offense starts a little slow and then takes off in the second half. But with Washington undergoing another defensive makeover, it would be helpful if the offense has a strong start to the season. If that doesn’t happen, what will Washington rely on at the start?

After a poor showing in limited action against Baltimore, the first-team offense looked bad for a longer stretch against Green Bay at FedEx Field. In its first five possessions, Cousins and Co. managed just 76 yards and three points, which came after Niles Paul recovered a fumbled punt. On that scoring drive, the offense didn’t gain a yard. It ran three frustrating plays and then watched Dustin Hopkins kick a 34-yard field goal.

Even after the Packers substituted most of their starters, Washington had little success. Finally, during the starting offense’s sixth drive, against Green Bay’s backups, our curiosity was satisfied: What would it take for Washington to reach the end zone?

It took a 43-yard pass from Cousins to tight end Vernon Davis. And later, with 17 seconds left in an exasperating first half, Cousins hit Jamison Crowder for a four-yard touchdown pass on fourth down to stop the ridiculousness.

At least the first-team offense left the game with the memory of doing something positive.

Then again, it was against a bunch of special teams players.

In that final drive, the offense gained 78 yards on 10 plays. In Washington’s first 24 plays, it managed just 76 yards. Cousins wound up 14 for 23 for 144 yards and one touchdown, but at one point, he was just 8 for 16 for 67 yards.

“It took a little while,” Gruden said. “We stuttered and sputtered and missed a few throws.”

Cousins and Pryor, his new big target, are still searching for a rhythm. Pryor caught one pass for 11 yards, and he let another go through his hands. Cousins also missed him on what could have been a touchdown, throwing an inaccurate pass to Crowder underneath instead.

It’s no shock that Cousins and his receivers aren’t sharp. Washington is trying to replace two 1,000-yard receivers, DeSean Jackson and Pierre Garcon. While the offense still has plenty of talent and Gruden’s system has been productive over the years, there was bound to be an adjustment. The problem seems even greater because Reed isn’t available. If anything, that’s the biggest lesson of the preseason thus far: Reed’s importance to this offense is at an all-time high. When he’s not available, it won’t be as easy to turn to the next man up. Washington will suffer more than it ever has without him.

But the passing game’s early struggles are understandable. It was more discouraging to watch the running game provide nothing. When Cousins was directing the offense, the running backs gained just 10 yards on 11 carries. Washington couldn’t run on first down, and Reed wasn’t on the field to catch those short passes to ignite drives. As a result, the offense had nothing it could bank on during early downs.

Gruden has an interesting task. Eventually, talent will take over, and Washington will move the ball. But the coach may have to be even more clever than usual to put these particular players in the best positions to succeed. Cousins is going to have to develop greater trust in some of his receivers over the next three weeks. And while Gruden’s system is still very sound, the system alone can’t replace the production of Garcon and Jackson. They will be missed. Garcon’s tough catches and possession-receiving gifts gave the passing game stability. Jackson’s speed and threat to score a touchdown at any time created space for everyone in a way that can’t be replicated, not even by Pryor.

“We all believe we’ve got a lot of work to do,” Cousins said.

So Gruden isn’t merely fitting prototypes into his way of doing things. These aren’t just new pieces for the same puzzle. The skeleton of a good offense remains. But how long will it take for this unit to reach its potential?

That question is growing more urgent every time you catch a glimpse of this Washington football team.