England forward Courtney Lawes is a doubt for the autumn internationals after being ruled out of Northampton’s 23-20 win over Gloucester on Friday.
The second row had a swollen knee after training in midweek and will have a scan this week.
Northampton director of rugby Jim Mallinder is “not sure” if Lawes will make England’s autumn Tests, with South Africa first up on 12 November.
Second row options Maro Itoje and George Kruis are also injured.
As well as those two, England head coach Eddie Jones is also definitely without James Haskell, Jack Clifford, Mike Williams and Sam Jones.
“Courtney has a bad knee – he did it a couple of weeks ago and missed the Montpellier game,” Mallinder added.
“We thought it had improved and he played last week with no problem, but midweek in training it reacted so we will have to have a scan on it to see the extent of the injury.
“Fingers crossed there is not too much damage and he will be ready in a couple of weeks.”
After facing South Africa, England play Fiji on 19 November, Argentina on 26 November and Australia on 3 December, with all matches at Twickenham.