Jose in warning to Euro rivals

But Mourinho is realistic enough to accept that at some stage Chelsea's undefeated start to the season is likely to end. "I always think positive and believe in good things," he said. "But the bad days always arrive - and I am ready for them."

To be truthful there are few signs at the moment of any dark clouds on the horizon. Chelsea are playing with confidence, desire and great defensive discipline, even if the end product lacks a little charm.

Two goals conceded in nine games is an impressive statistic and suggests the kind of defensive consistency that is essential for any team striving to win Europe's most prestigious prize.

John Terry, for instance, played a major role in ensuring that Porto never seriously threatened to beat Chelsea last night. Sven-Goran Eriksson, who has Sol Campbell and Rio Ferdinand available for the World Cup a qualifiers against Wales and Azerbaijan, will have to give his centre-back pairing a lot of thought after reading Tord Grip's report of Terry's performance last night.

But it was the energetic striker Eidur Gudjohnsen who starred in a first-half of indifferent quality. His diligent harassing of the Porto back four was the first line of Chelsea's deep defensive strategy.

The central midfield partnership of Frank Lampard and Claude Makelele provided the second stage, though Lampard also found the time in the second half to kick-start many of Chelsea ' s attacking moves.

After the match the Porto manager, Victor Fernandez, acknowledged the value of Lampard's deliveries from set pieces. "One of our problems was Lampard at free kicks because we were playing against some of the best headers of the ball in Europe," he said.

But it was Gudjohnsen who set Chelsea on their way as early as the seventh minute. He latched onto a clever pass from Damien Duff and hooked the ball over a couple of defenders to Alexei Smertin, who carefully drove the falling ball into the net.

Twenty minutes later, keeper Vitor Baia saved bravely at the feet of Duff but, that apart, Chelsea created little of note in the first half. But soon after the re-start, Didier Drogba headed a Lampard free-kick over the bar and moments later rose high again, twisting in the air, to get his head to a free-kick from Duff.

This time the ball flew into the net and Baia, having mistimed his challenge, didn't know much about it. Nor, I suspect, did Drogba. But they all count. This was his fifth goal of the season.

Trying to salvage the match, Porto threw on substitutes. One of them, Benni McCarthy, beat Petr Cech for only the second time this season after the Chelsea goalkeeper had blocked, but failed to hold, a stinging drive from another substitute, Carlos Alberto.

Mourinho was clearly unhappy with this breach of his defensive security and Terry tried to make amends in the 70th minute, bravely diving full length to head home a free- kick from Lampard. That, at least, was a goal made in England.

Mourinho, who had been spat at before the match by Portuguese fans, dismissed the incident and instead wanted to talk about Chelsea's growing challenge for the European title.

"We have six points and we've just beaten the champions of Europe," he beamed. "We're already in a fantastic position to go through to the next stage." No one is arguing with him - but the rest of Europe is now watching him warily.