Los Blancos will once again be missing Eduardo Camavinga, who picked up a knee injury ahead of the UEFA Super Cup in the early stages of August, but the Frenchman is now closing in on a return to fitness.
David Alaba remains a long-term absentee with a serious knee injury, while Brahim Diaz (hip) and Dani Ceballos (ankle) are still unavailable for selection.
Jude Bellingham played 80 minutes of the Champions League clash with Stuttgart last week on his return from injury, and the midfielder is in the squad for the clash with Espanyol.
Endrick scored his second goal for the club in the 3-1 success over Stuttgart, with the Brazilian becoming Real Madrid's youngest-ever Champions League goalscorer in the process.
Camavinga, Ceballos, Alaba, Diaz are absent for Real Madrid
"He will be a starter in one of the next few games and in many of Madrid's games. With the quality he has, it's obvious. He is very humble, talks little and works a lot. I like that," Real Madrid boss Carlo Ancelotti told reporters when asked about Endrick.
Ancelotti also confirmed that Camavinga is close to returning, with the Frenchman due to feature in team training next week.
"Camavinga is very close. He will work with the team next week and he is working very well. He is very important for us. It allows us to have more resources and he will bring a lot to the team," he added.
Eder Militao did not start against Stuttgart in the Champions League, but the Brazilian is expected to come back into the XI on Saturday, replacing Lucas Vazquez in the process.
Real Madrid squad vs. Espanyol:
Courtois, Lunin, Fran; Carvajal, Militao, Vazquez, Vallejo, F Garcia, Rudiger, Mendy; Bellingham, Valverde, Madrid, Tchouameni, Guler; Vinicius, Mbappe, Rodrygo, Endrick