England flanker Tom Wood will not know the extent of a foot injury until he receives the results of a scan later this week, BBC Look East understands.
The 25-year-old is being assessed by his club Northampton Saints and it is unknown if he will miss the start of England's Six Nations campaign.
Nine-time capped Wood is one of the leading candidates to captain Stuart Lancaster's side.
Saints team-mate Calum Clark has been cleared to play after a hand injury.
The 22-year-old back-row forward, who has received his first England call-up, had been suffering from an infection in his hand following surgery to a broken thumb, but will feature in this weekend's Heineken Cup clash with Scarlets.
The pair are among a group of eight Saints players named in Stuart Lancaster's Elite Player Squad.
Former England skipper Lawrence Dallaglio has touted Wood as one of the potential candidates to replace Mike Tindall as the national captain.
Lancaster is already poised to be without fly-half Toby Flood for the Six Nations opener against Scotland on 4 February, while centre Manu Tuilagi and lock Courtney Lawes are in a race against time to recover from injury problems.