Swansea defender Alfie Mawson has undergone knee surgery, leaving his World Cup hopes seemingly over.
Mawson had the operation after Swansea's relegation from the Premier League was confirmed by Sunday's 2-1 home defeat to Stoke.
Swansea are waiting to discover the full extent of the injury, but it is feared Mawson will be out until the start of next season.
The England under-21 international won a first call-up to the senior squad for the friendlies with Netherlands and Italy in March, but has yet to win his first cap.
Mawson had been considered an outside bet to make Gareth Southgate's squad, which will be named on Wednesday.
The injury is thought to stem from when he pulled up just before Swansea's FA Cup tie at Sheffield Wednesday in February.
But the centre-back, one of only 10 players to play every minute in the Premier League this season, played through the pain barrier during the last few months of the campaign.
The 24-year-old was one of Swansea's best players in a turbulent campaign and has been linked with a summer move away, with West Ham reportedly interested.