Andrew Sheridan is set to miss England's Grand Slam bid after suffering a torn calf.
The Sale loosehead prop was forced off in the first half of England's 17-9 victory over France on Saturday.
England manager Martin Johnson said Sheridan faced between two and four weeks out.
Sheridan has suffered a grade two tear of the calf and has returned to Sale from England's training camp in Oxford.
Fly-half Toby Flood has undergone a scan on his injured Achilles and England remain confident he will be fit to face Scotland at Twickenham on March 13.
England's final game of the RBS 6 Nations is against Ireland in Dublin six days later.
Johnson said: "Sheridan has a grade two tear, so it is not good. I think he is probably out of the championship. I am hearing it is two to four weeks.
"He is probably out of the championship unless there is some huge improvement very quickly.
"Flood is okay. He has a bit of Achilles tendon soreness. We think he will be fine (to play Scotland) but we will be very cautious with him this week."