Toni Kroos, Eden Hazard, Federico Valverde and Dani Carvajal were all absent from Real Madrid training on Wednesday.
All four first-team stars are suffering with injury and the club released a statement saying the players were "continuing with their recovery processes."
The La Liga giants are preparing to take on Eibar at the weekend before welcoming Liverpool to the Spanish capital next week.
The Reds will take on Zinedine Zidane's men in the first leg of their Champions League quarter-final on Tuesday.
Hazard will miss the clash having suffered with a series of injury problems this season while right-back Carvajal is a major doubt for both legs due to a hamstring problem.
Meanwhile, the availability of dynamic 22-year-old Valverde is touch and go as he recovers from musclar problems while his centre-midfield partner Kroos is also a doubt after withdrawing from the Germany squad due to an abductor issue.
A statement on Real Madrid's website read: "The players began with activation exercises without the ball and carried out fitness and possession work. They then focussed on pressing, passing and finishing in mini-goals. Finally, they played a timed small sided games.
"Carvajal, Hazard, Kroos and Valverde continue with their recovery processes."
