Cristiano Ronaldo is emerging as the player of this tournament, or at least the striker other teams have to find a way to stop, yet it does Portugal a disservice to depict them as a one-man team.

Even if by his recent standards this was a quiet, unflashy, almost workmanlike performance from the Portuguese captain, he still hit a post at both ends and scored his third goal of the competition just when his side needed it. The Czechs could not keep him out for 90 minutes, though the only goal was a team goal, with Ronaldo merely supplying the emphatic finish.

That is not to say he did not deserve the headlines and another man of the match award but Portugal do not simply channel everything through him. They had to wait 79 minutes for their breakthrough, and when it came it was a result of patient passing that moved the ball from one side of the pitch to the other, and exemplary movement and vision from Nani and João Moutinho.

It was beginning to look as if the Czechs' dour, dogged commitment to defence would at least take the tie to extra time but that is a dangerous game to play against a side with such silky attacking runners as Portugal. They will face a far more searching examination against Spain or France in the semi-final, though Ronaldo is probably looking forward already to the space he will find against teams who actually send players up the field in search of goals of their own. The Czech Republic played the only trick they knew and it did not work. Confronted by constricted space and a massed defence Ronaldo still found enough chances for a hat-trick, all the time seemingly holding something in reserve for greater challenges ahead. If this is to be Portugal's year, and it might be, Ronaldo knows the crucial test is coming up in Donetsk next week.

Portugal too sat back at first, as if they had heard of the theory that they do not perform well against opponents who defend deep and were prepared to play the Czechs at their own game. You could tell that approach did not appeal to Ronaldo, who reacted with all the toys-out-of-the-pram petulance of old when the first ball he chased into the Czech half beat him and rolled into touch. As captain, and already carrying a booking, Ronaldo seemed alarmingly pumped-up considering the game was seven minutes old, though the rest of his team-mates were in danger of being too laid back for their own good. When no one bothered to check Michal Kadlec's run out of defence the centre- half carried the ball all the way into the Portugal penalty area and tried his luck with a shot. Portugal's casual surrender of possession on half way allowed Vladimir Darida to set up the first chance of the game for Milan Baros.

Once in the first half Ronaldo flicked a pass to Moutinho and accelerated through the centre to reach the return, instantly finding the space the Czechs were trying to deny him but on this occasion being brought back for a shove on the last defender.

The Czech defence faced a similar dilemma to Holland's in the last group game. They knew exactly what Ronaldo would try to do but that did not make it any easier to stop him. His next two attempts went wide, the first an improvised overhead kick when the ball came through to him unexpectedly, the next an ambitious shot direct from a free-kick 30 yards out that he caught well but Petr Cech had covered anyway.

Cech was beaten when Ronaldo brought an undistinguished and uneventful first half to a close by almost putting his side in front at the optimum moment. Taking a high ball forward on his chest in the area he effortlessly held off Kadlec while at the same time turning to shoot, only to see his crisp low drive rebound from the foot of a post.

Hugo Almeida should have put Portugal ahead at the start of the second half instead of wasting an excellent cross by Raul Meireles, before Ronaldo struck the outside of the post again from a free-kick.

By the hour stage the Czechs were playing with 10 men behind the ball and seldom getting out of their own half. Nani then Moutinho brought saves from Cech with shots from distance but clearly something special was going to be required. Ronaldo duly obliged with a diving header from near the penalty spot that Cech had no chance of saving, much to the delight of the watching Portuguese greats Luís Figo and Eusébio. He then ran to the nearest camera to blow kisses to the millions of fans around the world.

He should really have been acknowledging the excellent Moutinho's part in the proceedings, though his team-mates are probably used to him by now.