Atletico hold a 10-point lead at the top of the standings in La Liga with a game in hand
Atletico Madrid forward Joao Felix has become the club's third player to test positive for COVID-19 in the last week.
A statement from the La Liga leaders said the Portuguese, who cost Atletico a club record 126 million euros ($151.39 million) in 2019, was isolating at home in line with the league's protocol.
He is set to miss Monday's game at home to Celta Vigo along with defender Mario Hermoso and winger Yannick Carrasco, who each tested positive last week.
Atletico hold a 10-point lead at the top of the standings with a game in hand.