England defender John Stones is a doubt for his side's Euro 2024 opener against Serbia on Sunday due to illness.

The centre-back missed England's training session on Thursday, with goalkeeper Dean Henderson confirming he has a sickness bug and has been confined to his room.

Even if Stones can start Sunday's game, it is unlikely he will be able to complete the full 90 minutes.

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The FA protocols enforce players with illnesses to be quarantined to their bedrooms. Stones will be closely monitored by the FA medical staff this week.

Image: Stones picked up an injury against Iceland but is now ill The injury loss to Harry Maguire earlier this month means England could be without both of their starting defenders from the last three major tournaments for the opener against Serbia.

Luke Shaw, who returned to England training this week after being out since February, is unlikely to play against Serbia, but Southgate revealed the left-back could return for the second game against Denmark on June 20.

Marc Guehi is likely to partner Stones at centre-back in this tournament, having picked up 11 caps for his country prior to the Serbia game.

Who are the options to replace Stones if he is out? Image: Marc Guehi (left) and Lewis Dunk (right) could be starting centre-backs vs Serbia Ezri Konsa - The Aston Villa defender replaced the injured Stones at centre-back at half-time of the friendly defeat to Iceland on June 7. Konsa started England's previous three games before that, albeit at right-back.

Lewis Dunk - The Brighton defender started for England in defence against Bosnia & Herzegovina. Dunk is the most experienced back-up option in terms of age, but this is his first major tournament and made errors against Belgium and Brazil in March.

Joe Gomez - Ten out of Gomez's 15 England caps have come at centre-back, but the 27-year-old has not started a game for the Three Lions since August 2020.

'Guehi could be England's senior centre-back' Sky Sports News' Rob Dorsett in Germany:

"We know Stones has had an ankle problem since the final warm-up game against Iceland at Wembley. He had to come off at half-time and arguably could have come off before that.

"His absence from training on Wednesday is because he was ill. Stones has started one Premier League game for Manchester City since the middle of March. He needs full, intensive training and game time.

"He was denied game time against Iceland due to injury which forced him off at half-time. He is now not training with England. The illness, we don't know how long it will continue for, but if Stones is not able to train with England over the next couple of days, Southgate will have to take a view about whether he is fit, possible and available.

"Lewis Dunk could be one of the first players to come in and then it would be an inexperienced partnership of Marc Guehi and him. The other alternatives are Ezri Konsa - who has largely been used at right-back - and Joe Gomez.

Image: Would Ezri Konsa come in at centre-back if Stones is out? "Guehi is now looking very important for England. He has only reached double-figure caps for England and has been mostly used off the bench. With Harry Maguire not here and not being fit to travel, and with real concerns over Stones, he could be the senior centre-back to start the European Championships."

Stones fitness adds to defensive concern Sky Sports' Chris Sutton: "Like everybody else, I'm so excited about England's midfield and going forward. I think we have the best attacking line-up in the tournament but most pundits and people feel the defence is an area of concern.

"It's good to see Luke Shaw back in training and he's going to have to get up to speed quickly. Kieran Trippier is a right-footed left-back so it'll be interesting to see how that works.

"I know he's played there before but defensively it's an area of concern. There are some wonderful attacking players who can hurt any team but John Stones' fitness is a worry."

"Somebody has to emerge. Everybody felt the centre-half partnership starting against Serbia would be Stones and Marc Guehi but if Stones is unwell, whether it's Lewis Dunk or Ezri Konsa, they're going to have to form a formidable central defensive partnership for England to really go far in this tournament."

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