Real Madrid's Belgian goalkeeper Thibaut Courtois celebrates his team's second goal during the Spanish League football match between Real Madrid and Barcelona at the Santiago Bernabeu stadium in Madrid on March 1, 2020. (OSCAR DEL POZO / AFP)

MADRID - Real Madrid goalkeeper Thibaut Courtois is an injury doubt for his side's Champions League return leg away to Manchester City next week.

The Belgian left the pitch in obvious pain at the end of his side's 2-1 defeat away to Betis on Sunday, with a possible problem in his left abductor muscle.

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If Courtois has suffered a muscle injury that would rule him out of Friday's Liga Santander game at home to Eibar

Real Madrid were unable to carry out tests to confirm or rule out an injury on Monday as the area was still inflamed and it will not be until Tuesday that they discover the extent of the problem.

Courtois reported to Real Madrid's Valdebebas training center on Monday for treatment, but so far the club has not issued any statement over his state.

If Courtois has suffered a muscle injury that would rule him out of Friday's Liga Santander game at home to Eibar and make his presence against Manchester City in the Ethiad Stadium highly unlikely.

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Alphonse Areola is Courtois' substitute at the club, but the player who is on loan from Paris Saint Germain has failed to convince this season and has conceded nine goals in eight appearances - four of which came in his last match, where Real Madrid were knocked out of the Copa del Rey 4-3 at home to Real Sociedad.