Chelsea's uncharacteristically off-colour performance at Manchester United on Sunday has partly been put down to a bug that affected a number of key members of Antonio Conte's squad and ruled Marco Alonso out of the game at Old Trafford.
Alonso was still suffering the effects of the virus on Saturday night and, despite being named in the starting line-up at United, complained of feeling ill after the pre-match warm-up. Chelsea's medical staff duly assessed him in the away changing-room and the wing-back was withdrawn from the team, with the league leaders going on to lose the match 2-0 to leave their advantage at the top trimmed to four points from Tottenham Hotspur with six games still to play.
Alonso's late withdrawal forced César Azpilicueta to fill in on the left, with Kurt Zouma drafted in as a right-sided full-back and clearly affected the balance of Conte's team, yet the Spaniard was not the only Chelsea player still suffering from the virus which had set in within the squad towards the end of last week.
One theory that has been considered by the club is that the bug had actually spread through the squad at a team bonding meal – one of a number arranged by Conte over the course of the campaign to strengthen the group – last Thursday evening.
Victor Moses, only just returned from a calf injury, had also been hampered and, having started the game, had to be withdrawn nine minutes into the second half prompting further disruption to the visitors' approach. Diego Costa is also understood to have been unwell and, like Moses and Alonso, had missed training at the back end of last week ahead of the trip to the north-west.
The striker declared himself fit but struggled to make much of an impact during the game, embroiled as he was from early on in tussles with Eric Bailly and Marcos Rojo in the hosts' back-line.
Costa, who was eventually booked for a foul on Paul Pogba, has now failed to score in five consecutive Premier League games for the first time in his career in English football – his last club goal was at West Ham in the first week of March – but, while Conte has consistently praised the Spain international's work-rate over recent weeks, he appeared to lack his normal energy levels at times on Sunday.
The hope at Chelsea is all will be fit to feature in Saturday’s FA Cup semi-final against Spurs, when the league leaders hope to inflict psychological damage on their nearest rivals in the title race. Thibaut Courtois, who hurt his ankle while playing basketball at a Chelsea promotional shoot for the NBA last week, is also hopeful he will have proved his fitness for the game at Wembley
Guardian services.