Robert Griffin III (above) and Redskins were stymied by penalties in loss to Panthers (John McDonnell/The Washington Post)

The Redskins entered Sunday’s game against the Carolina Panthers as one of the league’s most penalized teams. That trend continued as they took 13 penalties for 97 yards in a 21-13 loss.

“To play like we did today was disappointing,” Coach Mike Shanahan said. “The penalties that we had, it’s hard to keep drives going…. It’s hard to win those games, especially with as many penalties as we had. We stopped ourselves a number of times.”

Left tackle Trent Williams said the penalties undid the Redskins’ offense.

“We moved the ball,” Williams said. “Like I said, we still had over 100 yards rushing. Robert [Griffin III] threw the ball great. They had a good scheme. You can’t take nothing away from them. We committed a lot of penalties. We helped them beat us. Other than that, man, I think overall we moved the ball okay.”

Williams called the performance “very frustrating” and said: “It felt like every time we got something going, there was a flag on the play. You know, the refs beat us up a little bit. We had to score three times down there in the red zone to try to get the game within reach. I mean, it was a lot frustrating things.”

The Redskins twice had touchdowns nullified by penalties on their next-to-last possession of the game before scoring on a two-yard touchdown run by reserve running back Evan Royster with 1 minute 28 seconds to play.

“I call it focus,” Williams said. “It’s not the discipline. We’re a disciplined team. Some of the calls were real touchy. But we can’t do nothing about that. That’s out of our hands. We definitely could focus in better and kind of trim down on the penalties.”

Said Shanahan: “That’s what gnaws at you, when you stop yourselves.”

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