Northampton lock Courtney Lawes will miss England’s autumn schedule with an ankle injury that will keep him out for about 12 weeks.
The 31-year-old is set to have surgery on the injury he sustained during the Premiership defeat by Sale last month.
Lawes was substituted in the ninth minute after competing for the ball in the air and falling awkwardly.
Leaders England end their disrupted Six Nations campaign in Italy on Saturday, 31 October.
Lawes, who has 85 caps, started three of the four matches before the tournament was postponed in March amid the coronavirus pandemic.
England defence coach John Mitchell told BBC Sport: “I feel for him but he’s resilient enough to be able to manage himself through this time, he’s got a lovely family so he will get the balance.
“He’s a player who leads through his actions – very physical – but it’s now an opportunity for somebody else to take. Once Courtney gets healthy and should the next person take it and create an outstanding level, we are going to be even more healthy through the competition.”
England head coach Eddie Jones will also be without Sale centre Manu Tuilagi for the rest of the competition, after he ruptured his Achilles tendon during the same game.
With the experienced Lawes and Tuilagi missing, Jones has named 12 uncapped players in a much-changed training squad.
England face the Barbarians on 25 October, before completing the 2020 Six Nations against Italy and then playing four games in the Autumn Nations Cup.
|25 October, 14:00: England v Barbarians, Twickenham|
|31 October, 16:45: Italy v England, Stadio Olimpico, Rome|
|14 November, 15:00: England v Georgia, Twickenham|
|21 November, 15:00: England v Ireland, Twickenham|
|28 November, 16:00: Wales v England, TBC|
|6 December, 14:00: England v TBC, Twickenham|
Chris Jones, BBC rugby union correspondent:
With 85 caps over the course of 11 years, Lawes is one of the great England players of his generation – and has established himself as a real leader in Eddie Jones’ squad.
Usually a position of depth and strength, Jones is now short of a couple of experienced second rows, with Lawes injured and George Kruis off to Japan.
Maro Itoje, Joe Launchbury and Charlie Ewels remain though, while the uncapped Northampton pair of Alex Moon and David Ribbans have a chance to impress in this week’s training camp.
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