Redskins coach Mike Shanahan expressed disappointment in Robert Griffin III’s running ability Sunday night.

“He only averaged 10 and a half yards per carry,” Shanahan said. “I was hoping he would average more.”

Yes, he was kidding. Griffin rushed six times for 63 yards and ran well enough to hurt the Cowboys as well as set up zone read runs for running back Alfred Morris.

But even Shanahan said he’s not sure when Griffin will return to, well, being Griffin. He played his second game since missing a week after spraining the lateral collateral ligament in his right knee.

“The LCL will take time,” Shanahan said. “Is it a month, month and a half?”

Shanahan said it’s hard for a player to return and run as fast as they can after spraining their knee. And, he said, Griffin’s knee is not hurting him more than he’s let on — Shanahan bases that on how he’s looked in practice and how he cuts.

“Doctors say he’s 100 percent and we don’t have to worry about him reinjuring that LCL,” Shanahan said. “That brace helps him out mentally to know that he’s not putting too much pressure on it. Sometimes that’s why it does look different when he cuts. I think it bothers him a hair, but it’s something he has to wear. Hopefully it gets better and better.”