Mason Mount, Fikayo Tomori, Tammy Abraham and Christian Pulisic had already been confirmed to be in quarantine. The four had been together during their vacation this month on the Greek island of Mykonos – photos posted by the players on social media reveal they met during their stay.
The other four currently in quarantine and absent from the preseason are Jorginho, Ross Barkley, Emerson and Michy Batshuayi.
None of the eight are back in training at Cobham and will have to start their preparations by working alone as they did at the start of the lockdown. Abraham and Mount were selected by Gareth Southgate for the England squad for the Nations League matches against Iceland and Denmark, but their involvement in those matches is now in doubt.
Chelsea start their season at Brighton on September 14 and face Liverpool at home five days later. As the club faced the resumption of the previous season, one of its key players, N’Golo Kante, was skeptical of the game and had to be convinced of the safety of the measures taken by the Premier League.
Players were given clear advice on where to go on vacation for their short break this summer and Mykonos was seen as a good option as it was not subject to the UK government’s 14-day quarantine measures.
Chelsea declined to comment.