Real Madrid will travel to Olympiakos for its Champions League fixture with a significantly weakened backline, as a series of injuries threatens the team’s attempt to snap a three-match winless run.

The club announced Tuesday that goalkeeper Thibaut Courtois will miss the game due to a gastrointestinal virus. Coach Xabi Alonso will have only one natural center back — Raúl Asencio — available for Wednesday’s fifth-round match in the league stage of the competition.

Dean Huijsen has been sidelined with a knee problem and will not make the trip to Greece. Antonio Rüdiger remains out as he continues his recovery from a muscle injury, while Éder Militão is unavailable after suffering an injury while on duty for Brazil during the international break.

French midfielder Aurélien Tchouaméni is expected to fill in as a makeshift central defender, a role he has taken on before when required.

Madrid currently sits seventh in the league phase with three victories and one defeat. Olympiakos, meanwhile, is struggling near the bottom after registering two draws and two losses.

Real Madrid is coming off a 2-2 draw against Elche in La Liga on Sunday, following a goalless draw with Rayo Vallecano in the previous round and a 1-0 defeat to Liverpool in the Champions League. Alonso’s squad had opened the season in strong form, winning 13 of its first 14 matches.