Santos denied the omission was due to the four-time Ballon d’Or winner’s relatively meagre goal-scoring start to the Spanish league season.
Ronaldo has scored only one goal in six La Liga games for Real Madrid, although he has been on fire in Europe with six goals in four matches.
“Do you think that would be a reason to leave out Ronaldo? No, impossible,” Santos said of the former Manchester United star’s league form.
Portugal face Saudi Arabia and the United States in a pair of low-key friendlies on November 10 and 14.
Ronaldo is likely being merely rested, as he was for Portugal’s final Confederations Cup match in Russia in June, a meaningless third-place play-off victory over Mexico.
Santos’s 24-man squad is also missing several other stalwarts including goalkeeper Rui Patricio, defender Jose Fonte, midfielders William Carvalho, Joao Moutinho and Andre Gomes and winger Ricardo Quaresma.
“Some aren’t there simply to rest while others are injured,” explained Santos.
Squad:
Goalkeepers: Anthony Lopes (Lyon/FRA), Beto (Goztepe/TUR), Jose Sa (FC Porto).
Defenders : Edgar Ie (Lille/FRA), Joao Cancelo (Inter Milan/ITA), Pepe (Besiktas/TUR), Kevin Rodrigues (Real Sociedad/ESP), Luis Neto (Fenerbahçe/TUR), Nelson Semedo (Barcelona/ESP), Ricardo Pereira (FC Porto), Ricardo Ferreira (Braga), Antunes (Getafe/ESP).
Midfielders: Bernardo Silva (Manchester City/ENG), Bruno Fernandes (Sporting Lisbon), Danilo Pereira (FC Porto), Joao Mario (Inter Milan/ITA), Manuel Fernandes (Lokomotiv Moscow/RUS), Rony Lopes (Monaco/FRA), Ruben Neves (Wolverhampton/ENG).
Forwards: Andre Silva (AC Milan/ITA), Bruma (RB Leipzig/GER), Eder (Lokomotiv Moscow/RUS), Gelson Martins (Sporting Lisbon), Goncalo Guedes (Valencia/ESP).
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