Robert Griffin III has misfired on several throws against the Broncos. (Jack Dempsey/Associated Press)

Despite facing a Denver Broncos defense that ranks among the worst in the league against the pass, Robert Griffin III and the Redskins struggled in that department on Sunday, managing a season-low 154 yards through the air.

Griffin completed a season-low 50 percent of his passes (15 for 30) while throwing for 132 yards, one touchdown and two interceptions while getting sacked three times. Backup Kirk Cousins took over when Griffin left the game with a knee injury, but completed just 5 of 9 passes for 48 yards and two interceptions  one returned for a touchdown.

The Redskins this season rank 12th in the league with 1,800 passing yards, but when it comes to completion percentage, the team is 21st in the league at 58.8. This represents a significant drop-off from last season, when the team owned the sixth-best completion percentage in the league at 65.8.

Asked to pinpoint the reason behind the struggles, Coach Mike Shanahan said, “I think it’s a little bit of everything. You take a look at sometimes it may be a quarterback’s read, other time it may be protection, the next time it may be a dropped ball. The offense is a little bit different than what it was a year ago. It’s a combination of all those things.”

All of those elements were in play on Sunday as Griffin underthrew and overthrew his targets, and pass-catchers Santana Moss, Aldrick Robinson, Jordan Reed and Leonard Hankerson all had drops.

At times this season, Shanahan has attributed some of Griffin’s struggles in the passing game to his lack of an offseason of working with his coaches and receivers because of his rehabilitation from knee surgery. Griffin spent the first few weeks of the season working his way back into form after being held out of all of the preseason.

He now has seven games under his belt, but only once in the past three games has he completed better than 60 percent of his passes. But Shanahan said the quarterback still could be struggling because of a lack of offseason and preseason work. However, he reiterated that not all of the blame should be placed on Griffin’s shoulders.

“Everything’s a growing experience,” Shanahan said. “The more reps you get the better off you do get. I think we all understand that … It’s a combination of a lot of different things. Sometimes you may see a guy wide open and it may be a missed read. Sometimes it may be a dropped ball, in a case, it may be a missed assignment, or it may be the case of somebody getting beat. So it’s a combination of all those things that keeps a passing game going.”

Have a Redskins question? E-mail Mike Jones at with the subject line “Mailbag question” for him to answer it in The Mailbag on Tuesdays.

What’s ahead:

● Mike Jones’s mailbag mid-day on Tuesday.

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