Julián Álvarez missed yet another training session for Atlético Madrid on Friday due to a reported illness amidst ongoing transfer speculation.
Atlético said earlier this week that Álvarez, whose desire is to leave the club and join rivals Barcelona before the transfer window closes, was "unwell" on Wednesday.
The Argentina international also missed Thursday's session and did not join his teammates in the morning session on Friday.
Álvarez, 26, is also set to sit out Saturday's LaLiga game at Sevilla.
The former Manchester City forward came on as a second-half substitute in Atlético's 2-2 home draw against Villarreal on Sunday, his first appearance of the season.
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He was whistled by fans before, during and after the match at the Metropolitano stadium, before leaving the field alone as his teammates applauded the crowd.
Barça president Joan Laporta reiterated this week the club's interest in signing Álvarez but Atlético then hit back with a statement, saying there was a "zero percent chance" of Álvarez joining Barcelona and calling themselves "victims" in the saga, who had been "damaged financially and socially."
Álvarez had 20 goals in 49 appearances for the Rojiblancos last season.