Except for a short spell out of favour in 2019, the 32-year-old former Sheffield United defender has been a mainstay of Gareth Southgate's England, playing in the last European Championship final, the last World Cup semi-finals, and a Nations League semi-final.

But he went off injured in Manchester City's derby-day hammering of their neighbours United on Sunday, and has gone under the knife.

His club manager Pep Guardiola was unable to put a timescale on his recovery but Southgate is due to name his provisional squad on October 19, with England's first game at the World Cup on November 21.

His club-mate and fellow Yorkshireman Kalvin Phillips was already up against it after shoulder surgery last month.

"He will be a while out, I don't know (how long)," said Guardiola. "I cannot say anything else. We have to speak to the doctors. Hopefully he can get back like Kalvin."

Barnsley-born City defender John Stones picked up a muscle injury in September's game against Germany, but his prospect of being fit in time look much better.

England have an embarrassment of riches at right-back, but with Southgate appearing to settle on a back three going to Qatar, Walker was the first choice on the right of that set-up, as well as an option at wing-back or at full-back if he were to switch to a four. His pace balanced out what has for a long time tended to be an all-Yorkshire back four of himself, Stones and Harry Maguire.

INJURY: Kyle Walker received treatment during Sunday's Manchester derby

Maguire is also injured, struggling for game-time at club level and for form.

Eric Dier impressed at centre-back in September's Nations League games but is most likely to be used in the middle of the three, with fewer natural options on Maguire's left side.

But it would not be England without going into a major tournament without injury doubts over key players.

Former Sheffield United defender Kyle Walker joins Kalvin Phillips as major England doubt for Qatar World Cup