Atletico Madrid have confirmed Marcos Paulo has suffered a preseason injury.
The summer signing was not included in the squad for their friendly against RB Salzburg in Austria.
Atletico announced: "After the radiological tests to which the footballer has been subjected, he has been diagnosed with a muscle injury in the right thigh. It is pending evolution."
The Brazilian attacker had complained of discomfort in training on Tuesday.
It's understood he suffered a heavy blow in a bounce game to the affected area.
