Costa Rica’s Navas left the field in the dramatic last-eight win over Atalanta with a muscular issue and will miss Tuesday’s meeting against the German outfit.
Spain’s Sergio Rico, who has played just nine games this season, is set to start in Lisbon after having replaced three-time Champions League winner Navas against the Italians.
Midfielder Idrissa Gueye is a doubt for the club’s first top-tier semi-final since 1995 but Marco Veratti, Thiago Silva and Layvin Kurzawa took part in training despite suffering various problems.
Ander Herrera, Leandro Paredes and Marquinhos are coach Thomas Tuchel’s options to take the Senegal international’s place.
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