Chelsea manager Frank Lampard welcomed his squad back for pre-season this week ahead of the new season, with Chelsea’s first Premier League fixture on 14 September.
However, some Chelsea players have been forced to go into isolation due to coronavirus.
According to the Daily Mail, there has been an outbreak of coronavirus among the Chelsea squad after players travelled abroad.
Although Chelsea have not revealed the names of the players who have tested positive to Covid-19.
The Sun claim Mason Mount, Tammy Abraham, Fikayo Tomori and Christian Pulisic are all in quarantine after returning from Mykonos in Greece.
The Chelsea players are self-isolating as a precaution due to the outbreak at Chelsea.
There have been 12 new Covid-19 cases at 14 different clubs since last week, with players jetting across the world during their short-lived breaks between campaigns.