Isco, Marcelo, Luka Modric and Cristiano Ronaldo were all present for Real Madrid's training session on Tuesday morning.
The quartet had been released from international duty following a number of injuries, but it is believed that all four will be available for the weekend's clash with Villarreal in La Liga.
According to Football Espana, Ronaldo continued his individual recovery programme, while Marcelo, Isco and Modric worked indoors alongside Xabi Alonso.
Madrid have won each of their three league matches this season.
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