Former Manchester United and Aston Villa defender Dion Dublin believes that Cristiano Ronaldo has the potential to win the Euro 2012 tournament for Portugal.

The Real Madrid star, who is often criticised for not performing in major tournaments, has made a huge impact for his national side and netted the winner in Portugal's victory over the Czech Republic in last night's quarter-final.

"I think Cristiano Ronaldo, when he wants to be, can be the best on show by a mile," BBC Sport quotes Dublin as saying. "There have been a lot of good players.

"I think Bastian Schweinsteiger has done incredibly well and it is also hard to look past people like Xavi and Iniesta. They all just keep things very simple but what is simple to them is very effective to the team. They keep hold of the ball and then hit teams on the break.

"There have been a few good players and good performances but, if we are talking great players, then Ronaldo is a great player. Great players can win a game, good players can affect a game."

Meanwhile, Germany and Greece go head to head in the second quarter-final of the competition tonight.