Cristiano Ronaldo [Images], who has just won a Champions League and Premier League double with Manchester United [Images], could complete a remarkable treble of winners' medals by leading Portugal to victory in Euro 2008 [Images] this month.

The 23-year-old winger, who scored 42 goals in all competitions for United last season, will be the key as Portugal look to ease their way past co-hosts Switzerland [Images], the Czech Republic and Turkey in Group A in Basel and Geneva.

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Fans at those two venues will be in for a special treat if he recreates his club form for his country, who head into the tournament free of the pressures that burdened them somewhat as host nation four years ago.

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They froze in the final and were beaten by big outsiders Greece in Lisbon.

Portugal are coached by Brazilian Luiz Felipe Scolari, who said last week that Ronaldo could end the tournament as indisputably the best player in the world.

"We know that there might be some doubt over which club he might be playing for next season but I don't expect him to have too many sleepless nights over that during the tournament," Scolari said.

"Instead I expect him to have a great Euro 2008 and prove himself to be the best player in the world."

Portugal should have the class to finish in one of the first two places from the quartet and qualify for the quarter-finals, probably with the Czechs.

STORMED THROUGH

The latter provide the opposition for the Swiss co-hosts in the opening match of the tournament in Basel next Saturday.

Still coached by Karel Bruckner, 68, the Czechs reached the semi-finals of Euro 2004, disappointed with a first-round exit at the World Cup two years ago but stormed through their Euro 2008 qualifying campaign, finishing ahead of Germany [Images] at the top of their group.

Although midfielders Karel Poborsky and Pavel Nedved have now retired and Tomas Rosicky is out injured, the Czechs have probably the world's best goalkeeper in Petr Cech.

Cech was beaten by a Ronaldo header and then saved his penalty in the Champions League shoot-out when Manchester United triumphed over Chelsea in Moscow [Images] last month and their meeting in Geneva on June 11 should be fascinating.

Switzerland go into the tournament after a two-year diet of friendlies in which they have won nine of the 19 games they have played since the World Cup.

Some of their performances have been abject like the 4-0 home defeat to Germany in March and although coach Koebi Kuhn might be hoping that home advantage will boost his side's chances, it would be a surprise if their involvement continued after their last group match against Portugal on June 15.

Turkey, who face Portugal in their opening game in Geneva on Saturday evening, failed to qualify for either Euro 2004 or the World Cup two years ago, when an ugly post-match brawl in a playoff against Switzerland in Istanbul resulted in sanctions from FIFA.

They face Switzerland in Basel on June 11 in what is likely to be an equally decisive match -- hopefully with a more peaceful outcome.

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