Cristiano Ronaldo under mounting pressure to perform for Portugal at Euro 2012

Cristiano Ronaldo is certain to face a fierce backlash of public criticism if he is unable to prevent Portugal from crashing out of Euro 2012 on Wednesday.

The Real Madrid superstar, soccer’s biggest pinup and a challenger to Lionel Messi for the title of world’s best player, alienated many fans in his homeland with a substandard performance and petulant behavior during Portugal’s opening defeat to Germany on Saturday.

[Related: German fans chant 'Messi' outside Portugal's hotel]

Another loss, to Denmark in Lviv, would almost certainly eliminate Ronaldo and his colleagues from the tournament and give extra weight to the belief the 27-year-old loses his nerve when it matters most.

“The Portuguese public wants to know if Cristiano is finally going to perform for the national side,” said Vitor Serpa, chief editor of respected Portuguese soccer magazine A Bola. “Up to now, he has been more of an individual than a team player.”

Ronaldo is the most expensive player on the planet, having cost Madrid $131 million since he was signed from Manchester United in 2009. He has racked up an extraordinary 113 goals in 109 games for the Spanish club, a rate of one goal every 87 minutes of action.

In major tournaments for Portugal, though, his record is far less spectacular. Now in his third European Championships and having also played in two World Cups, Ronaldo has managed just five goals in 20 games in those competitions, a rate of one every six hours.

Supporters of Ronaldo argue that he deserves a little extra latitude because the expectations placed upon him when playing for Portugal verge on the unrealistic. However, this is a player who is no stranger to the spotlight and his difficulties at major events are odd, at the very least.

“We don’t ask Cristiano to solve all our problems,” said head coach Paulo Bento, somewhat defensively.

[Related: Cristiano Ronaldo quiet in Portugal's loss to Germany]

Now, a disconnect might be starting to emerge between Ronaldo and the Portuguese population, one that will only increase if Denmark, which already defeated the Netherlands in its opening game, can pull off a second straight upset.

Ronaldo was criticized following the loss to Germany in the first match, when he peeled off his captain’s armband and stormed down the tunnel at the end, instead of walking over to applaud Portugal’s traveling band of supporters like many other players.

A header from Mario Gomez was enough to give Germany victory, but Ronaldo grumpily insisted that Portugal was the better team and had deserved to win.

“Anyone who watched the match will have seen we were better than Germany,” he said.

Denmark was originally thought to be the weakest team in Group B, known as the Group of Death and featuring four of the top 10 teams in the FIFA world rankings. However, it defended impressively and rode its luck to stun the Dutch and will like its chances against Portugal, having outdueled Ronaldo and his pals during qualifying to top its group.

[Related: Denmark beats Netherlands despite controversial social media ban by coach]

Portugal needs a win to keep its hopes of reaching the knockout stage in its own hands and avoid an angry response when it returns home.

“We expect certain things of ourselves and of course we have ambitions to be successful in the tournament,” Bento said. “We must be strong in the mind and perform to our best. We will not panic, but we also know that we have to produce our best right now.”

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