Jamie George could be a doubt for England's Six Nations opener after suffering a suspected concussion in Saracens' Champions Cup defeat to Edinburgh.

The hooker had been yellow carded earlier in the half for a high tackle on Luke Crosbie which resulted in a head-on-head collision.

He was cleared by the Saracens medical team to return to the fray after his 10 minutes in the sin-bin but was subsequently stood down by the independent match doctor.

George faces a minimum seven-day stand-down period, with England starting their Six Nations campaign against Scotland on February 4.

"I don't know exactly what happened," said Saracens director of rugby Mark McCall, after the 20-14 loss.

"It appears that Jamie passed his HIA (head injury assessment) and someone has had a further look at it and thought it better that he were withdrawn from the game.

"And, of course, that's the right decision."

Dave Cherry and Pierre Schoeman crossed for Edinburgh while Blair Kinghorn added two penalties and the same amount of conversions, with Alex Goode kicking three penalties for Saracens before Ben Earl's late effort.

"We started the game really poorly - passive and lost," added McCall.

"Strangely enough, when we were down to 13 men, we showed what we should have been like with 15 men - that was really good.

"Our fight and our effort was unbelievable when down to 13. If you come away from home and give away 19 penalties then you're not going to win many matches.

"I'm not sure why we were as passive defensively as we were today because it's not like us."

Edinburgh head coach Mike Blair said he had wanted his team to kick the ball dead after the 80 minutes was up to settle for a six-point win when they needed to score again to secure a home draw in the last 16.

"We wanted them to kick it off," he insisted, with Edinburgh travelling to Leicester in the next round.

"We made that call. You don't always get these things right, but our view was that we had Sam Skinner in the sin-bin, we were playing into a stiff breeze and we had no momentum in our attack.

"We felt Saracens had the momentum in the last 10 minutes. So, the decision was that we had won three of our four Champions Cup games and beating Saracens, who had only lost one of their last 16 games, would give us a boost.

"We would have loved a home game, but we felt the odds were stacked against us - so we cashed in. We were aware of the situation, and we are comfortable taking the win.

"Saracens were going really hard at us in the breakdown and I just felt the odds were stacked against us."