Cristiano Ronaldo cut a despondent figure at full-time of Portugal's 1-1 draw with Iran and coach Fernando Santos believes it was down to the Real Madrid star feeling like he failed when having a penalty saved.
Portugal scraped through to the knockout phase of the World Cup in Monday's contest, Santos' men finding themselves involved in a dramatic encounter in Saransk.
Ricardo Quaresma gave them a first-half lead with a stunning strike and Ronaldo could have doubled their advantage after the break, but he saw the penalty he won saved by Ali Beiranvand.
He was then lucky to escape a red card, receiving just a booking despite referee Enrique Caceres consulting VAR when Ronaldo caught Morteza Pouraliganji with an elbow to the head.
Iran ultimately claimed a share of the spoils thanks to a late penalty of their own – VAR again playing a role as Cedric Soares was harshly penalised for handball – and Ronaldo trudged off the pitch at full-time looking bitterly upset despite his side securing a last-16 tie with Uruguay.
"I understand, it's normal," Santos said when asked about his star man in the post-match news conference.
"The best players in the world face that [disappointment] when there's no opportunity to really make [the difference], it happens.
"It hurts more to them than the others. They want to be the best and when they fail they get very upset."
Despite the seemingly damning evidence of Ronaldo's collision with Pouraliganji, Santos insists he was never worried about the prospect of his captain getting sent off, adamant the technology at Caceres' disposal justified the official's decision.
"I wasn't concerned," Santos said. "It seemed like a normal thing in the match.
"The referee did what he had to do, went to VAR twice, three times and gave a yellow card. I'd have to see it again to make a judgement, but I think it did its job."