Cristiano Ronaldo remains upbeat over Portugal's chances of qualifying for Euro 2020 as he insisted the reigning champion deserved to beat Serbia, while the captain also questioned the absence of VAR.

Ronaldo hobbled off with an apparent muscle injury in the first half of Portugal's 1-1 Group B draw at home to Serbia in Lisbon on Monday.

Portugal earned a share of the points after Danilo Pereira's stunning 42nd-minute equaliser cancelled out Dusan Tadic's penalty as the host was held to back-to-back draws.

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After its scoreless stalemate against Ukraine, Portugal is third and two points behind the leader, but Ronaldo lauded his team-mates after they were denied a penalty.

"Honestly, I think the team played well," Ronaldo told reporters. "We had many chances of scoring, we couldn't make it. It's a pity, obviously to draw two matches at home but I take the good side of things and I think today the team played better than against Ukraine. We created more opportunities to score, did everything to win, couldn't make it. We had the penalty, which was more than clear, and the referee didn't give it or didn't see it, but overall the team was fine."

Portugal thought it had been awarded a second-half penalty when Serbia full-back Antonio Rukavina handled in the area, only for referee Szymon Marciniak to controversially change his initial decision to award a spot-kick after consulting with his assistant.

The decision angered Ronaldo and head coach Fernando Santos, with the star Portugal skipper questioning the absence of the video assistant referee.

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"If you have VAR to all competitions, why not for a European qualifier? It's strange," Ronaldo said. "We weren't favoured today, that was a clear penalty and the referee should have given it, not take the decision of another one who was 40 meters away and didn't even see the play."

Ronaldo added: "We'll make all we can to guarantee that Portugal will be at Euro 2020. There's no need to be nervous or to lose the faith in this team.

"The fans have to believe in our players. The ones who watched the match, who know football, know that Portugal deserved to win both games but at football one wins only when the ball is in. The ball didn't get in, at the next games, it will."