Portugal will have to qualify for the next year's World Cup in Qatar via the play-offs after a stoppage-time header from Aleksandar Mitrovic secured a dramatic 2-1 victory for the Serbs at the Estadio da Luz.
It all appeared to be going swimmingly for the hosts when Renato Sanches opened the scoring inside two minutes, but Ajax star Dusan Tadic equalised 31 minutes later before the Fulham striker's match-winning moment.
The Daily Mail says as players and staff from both sides shook hands following the final whistle, Ronaldo was first approached by Serbia substitute Nemanja Radonjic, who shared a brief embrace with the Manchester United star.
Ronaldo then spotted Santos, 67, approaching and began shouting and gesticulating furiously with his arms, but the Portugal boss then walked off after a brief handshake with the 36-year-old.
Ronaldo then put his hands on his hips before making his way towards the other players and the tunnel with his dejection still clear for all to see.
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