England are facing an anxious wait to see if Joe Root will be able to take any further part in the second Test against Bangladesh in Dhaka.
Root was forced off the pitch during the evening session of day two after complaining of an upset stomach. He was subsequently isolated from the rest of the squad to limit any chance of contagion, driven back to the hotel on his own and confined to his room.
While the team management are hopeful that a night's sleep will help Root make a swift recovery, they will be anxious to see how he is on Sunday morning. Such is England's reliance upon him, their chances of chasing down their fourth-innings target on a demanding Dhaka pitch will be substantially diminished if he is rendered unavailable.
He is rated the No. 3 Test batsman in the world, top-scored in England's first innings and is the only member of their top four to reach 20 this series.
Given that nobody else in the squad has reported similar symptoms and everyone has eaten the same food - due to security fears, the team are obliged to eat in the hotel restaurants every day and in the players' dining room during the match - there is a theory that he may have contracted the illness in his role as the team's ball polisher.
Root is one of very few England players allowed to handle the ball when the team are in the field and it is noticeable that, after almost every delivery, it is returned to him to shine before it is returned to the bowler. As part of that process, Root often licks his fingers before transferring his saliva on to the ball. It is, therefore, possible that he could have picked up something from the ground or even the ball.
England may have missed Root in that role already. While they have unlocked Bangladesh's batting in previous innings by utilising reverse swing, it was noticeable on the second evening that their seamers were unable to gain any movement.
George Dobell is a senior correspondent at ESPNcricinfo