Defenders the key in Mourinho's masterplan

Porto hardly needed a reminder of the value of Ricardo Carvalho but they were given two before the European champions had barely got into their stride in last night's Champions' League match.

Porto hardly needed a reminder of the value of Ricardo Carvalho but they were given two before the European champions had barely got into their stride in last night's Champions' League match.

Before the game, the Portuguese international was presented with an award as the best defender at Euro 2004. Seven minutes into it, a yawning gap, which he would no doubt have filled last season, opened up at the heart of the Porto defence and the unmarked Aleksei Smertin gratefully drove Eidur Gudjohnsen's cross into the corner of the net to give Chelsea the lead.

For all the talk of Jose Mourinho's triumphant squad from last season forming a queue to rejoin their former manager during the summer, only Carvalho and Paulo Ferreira made the move to Chelsea, even if their transfers did create a minor landslip on Roman Abramovich's cash mountain. The fees, £20m and £13m respectively, might have been more than anyone else in Europe would have paid, but Mourinho knew the two players' importance to his plans.

Like Brian Clough, the manager with whom he has frequently been compared in recent days, Mourinho believes in building his teams from the back. The plan has certainly been working so far, with Benni McCarthy's consolation goal for Porto only the second Chelsea have conceded in eight competitive matches this season.

Ferreira and Carvalho are both unfussy players, quite ready to hoof the ball upfield or to pass it back to their goalkeeper when danger threatens. That was rare here, particularly in the first half, despite a fluid formation which gave Porto plenty of attacking options. While Luis Fabiano, who is Ronaldo's deputy in the Brazil team, was left to fend for himself during periods of Chelsea pressure, both Quaresma, on the right wing, and Derlei, playing just behind the lone striker, were always ready to go forward in support.

For half an hour, however, Fabiano was barely given a touch as Carvalho and John Terry closed down the Brazilian whenever he was in possession. On the only occasion when he found some space in a danger area, moving on to Diego's clever through ball, Costinha was unable to get on the end of his cross.

Derlei was said to be Mourinho's favourite player at Porto and there is already talk of the Brazilian moving next summer when he gets a Portuguese passport. Terry and Carvalho in particular gave him little opportunity to show his worth. Even when the ball was about to drop at his feet in a rare Chelsea lapse, Carvalho was quickly on hand to nip the danger in the bud.

Ferreira had less work to do on Chelsea's right flank, but as the game wore on Porto started to make some inroads and Mourinho jumped from his bench to issue urgent instructions to Terry midway through the second half. By then Chelsea were two goals up and Fabiano and Quaresma had been replaced by Carlos Alberto and McCarthy, who immediately started to give the Chelsea defence problems.

Petr Cech was forced to make a smart save to keep out a low drive by McCarthy and after 67 minutes the South African striker put Porto back in the game. Cech was unable to hold Carlos Alberto's powerful shot and McCarthy reacted faster than any of the defenders in a rare lax moment at the centre of the home defence. Three minutes later, however, the lead was restored and it was appropriate that it was a defender, Terry, who supplied the scoring touch. As Mourinho knows, defenders can be match winners.