Harlequins fly-half Marcus Smith is a doubt for England's Six Nations opener against Italy following an injury setback.
Smith sustained the injury during a training session on Monday and was seen limping off the field. He is set to undergo a scan to assess the extent of damage.
With Owen Farrell already unavailable, Smith's potential absence for the tournament opener will leave head coach Steve Borthwick with George Ford and uncapped Fin Smith as the options for the fly-halves in the squad.
England attack coach Richard Wigglesworth revealed the news on Smith.
"I have heard nothing on what he has done," said Wigglesworth.
"Hopefully very precautionary, the medical staff here are generally like that. I have not been updated on that, since I have been back but if he is not [fit] it would definitely be a blow for us.
"It wasn't a big incident, that's why I was hoping it was nothing much.
"He was just jogging, it was never extensive but he pulled up and happened to be right next to a physio when he did it by the sideline, so they just walked off after that. I saw him walk off but when you mentioned crutches, I wasn't aware of that."
Following the game in Rome on 3rd February, England will be locking horns with Wales at Twickenham Stadium on 10th February.