I think that he can be used in Europe by Real for the knock-out rounds.
17.18 One player from the above quota of three who has played UEFA club
competition matches for another competing club in the current season may
exceptionally be registered, provided that the player has not been fielded:
− in the same competition for another club
− for another club that is currently in the same competition.
Furthermore, if the player’s new club is playing in the UEFA Cup, his former
club must not have played in the UEFA Cup at any point in the current
season.
If I'm reading it correctly, a club that plays in CL, can register a player who played in EL previously in the season.
17.18 One player from the above quota of three who has played UEFA club
competition matches for another competing club in the current season may
exceptionally be registered, provided that the player has not been fielded:
− in the same competition for another club
− for another club that is currently in the same competition.
Furthermore, if the player’s new club is playing in the UEFA Cup, his former
club must not have played in the UEFA Cup at any point in the current
season.
If I'm reading it correctly, a club that plays in CL, can register a player who played in EL previously in the season.
Strange, I have heard of a few players who were deliberately left out of the team this round in order for them to be eligible for their possible new team (AZ & Anderlecht players come to mind).
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