Another four players and members of staff from three clubs tested positive for COVID-19, confirmed the English Premier League.
On May 25 and 26, these tests were identified in the third round, when swabs were given to 1,008 individuals.
“Players or Club staff who have tested positive will now self-isolate for a period of seven days,” read a statement say.
Italian players or Club employees who test positive will have to undergo the mandatory quarantine of 14 days.
In the Premier League, there are now 12 positive cases of coronavirus, following three test rounds.
This follows the six positives in Round 1 from three clubs in 748 tests while in the second round there were two positive ones from two clubs in 996 tests.
“For the fourth round of testing, the number of tests available to each club will be increased from 50 to 60.”