MANCHESTER, England (AP)England defender Kyle Walker is in doubt for this year’s World Cup after undergoing groin surgery this week.

The Manchester City player sustained the injury in the win 6-3 over Manchester United on Sunday. He was taken off the field in the 41st minute.

”As players we have to appreciate injuries are part and parcel of the game we love,” Walker wrote on Twitter above a picture of himself in a hospital bed. ”My operation on Tuesday was a success and now I can concentrate on my rehab and getting back to full fitness. I will be supporting my team mates every day in any way I can.”

City said in a statement on Thursday that the surgery was ”successful.”

The 32-year-old Walker had been a certainty for the England squad but coach Gareth Southgate now faces an anxious wait to see if the defender can recover in time to play in Qatar.

After the 5-0 Champions League win over Copenhagen on Wednesday, City manager Pep Guardiola said Walker faced a prolonged period out of action.

”It’s something abdominal and he will be a while out. I cannot say anything else,” Guardiola said. ”Kyle will be out for a bit. We have to speak to the doctors. Hopefully he can get (back for the World Cup) like Kalvin (Phillips).

”I know how important the World Cup is for the players but honestly I don’t know right now.”

Walker was a key figure in England’s run to the semifinals of the 2018 World Cup and the final of last year’s European Championship.

Southgate has plenty of options at the back in Reece James, Kieran Trippier and Trent Alexander-Arnold, but the loss of Walker would be a major blow to his World Cup preparations.

AP World Cup coverage: https://apnews.com/hub/world-cup and https://twitter.com/AP-Sports

James Robson is at https://twitter.com/jamesalanrobson