Chelsea are renowned for their fighting spirit, although sometimes they take it a tad seriously, and they needed to use every ounce of it at Stamford Bridge last night. Faced with an exit from the Champions League, having trailed 1-0 at half-time against FC Porto, they dragged themselves out of the mire to win 2-1. It was Chelsea at their stubborn, cussed best.

How Roman Abramovich, the billionaire Chelsea owner, will have trembled as he watched a sterile first-half display from his millionaire players. Yet José Mourinho, the Chelsea manager, roused his charges during the interval — against his former club — and Abramovich could breathe a sigh of relief. It was good old gladiatorial fare.

Mourinho could start a fight in an empty room, but for the fact that he loves an audience. The bigger the crowd, the more the preening Portuguese likes to play up. The Champions League is the biggest stage, his stage, and the competition a televisual platform on which to spout forth the oracle according to King José.

But the players love him for it. Mourinho sticks up for them, even when they stumble and fumble, as they did in the first half last night. He wraps them in cotton wool, protects them and imbues in them a sense of spirit, a musketeerial mantra that has served them well over the past three years.

All for one and one for all: hear it, feel it, breathe it. That is the Mourinho way, that is why the world witnessed a mass brawl at the end of the Carling Cup final in Cardiff ten days ago. When John Obi Mikel was perceived to be in trouble, his teammates rushed to his aid.

It made for an unedifying spectacle, with Chelsea and Arsenal charged by the FA with failing to control their players, but it demonstrated — not for the first time during Mourinho’s reign in West London — that togetherness is the key. Without it, little can be won, everything is lost.

Mourinho’s ethos permeates all sections of the club, even to the outer fringes of the first-team. Chelsea and Arsenal players were at it again on Monday night when they slugged it out in a repeat of the disgraceful scenes at the Millennium Stadium.

This time, it was in Hampshire, at the Recreation Ground, the home of Aldershot Town. Mart Poom, the Arsenal goalkeeper, dropped a cross and, hey presto, the teams produced out of a hat another maelstrom of mayhem.

This time, no sendings-off — and no managers on the pitch, either — but the overworked FA will again be studying video footage. A fine for each club can be expected.

If only Chelsea had shown similar fight in the first half against Porto; if only they had played as a unit rather than a rag-tag bunch of disparate individuals. No flying fists, errant elbows or booming insults were needed, just a collective effort in a common cause: qualification for the quarter-finals.

It was not there. What the Chelsea fans got, after rabidly waving their free blue-and-white chequered flags before kick-off, was a powder-puff performance. Chelsea started poorly, with Mourinho sitting quietly on the substitutes’ bench, and only raised a leg after Ricardo Quaresma had prodded Porto ahead in the fifteenth minute.

Even then, though, it was mostly a hotpotch of wasted approach work and wasted energy. Andriy Shevchenko, reemerging from his shell of late, had disappeared back into it long before half-time; Ashley Cole ran into blind alleys; Michael Ballack again struggled to impose himself.

Only Didier Drogba could have been spared Mourinho’s fury at the break. Perhaps, to a lesser extent, Frank Lampard, the captain, but it was Drogba alone who wholly typified the Mourinho mentality. For such a prolific goalscorer, his application and graft are remarkable. Shevchenko should be ashamed.

From the pit of despair, Chelsea hauled themselves back to parity in the 47th minute. Helton, the Porto goalkeeper, as good as threw Arjen Robben’s lame shot into the net and Chelsea were level. As the players celebrated, Mourinho barked instructions manically from outside his technical area. Eye on the ball, as always; the master motivator was back.

One was not enough, but the crucial second was destined to come. Ballack hit home with his left foot with 12 minutes to play to make it look like a straightforward win.