London - Diego Costa swung a right boot in desperation. There was a minute to go, and Chelsea were on the brink. The ball travelled low, through the legs of James Collins. Adrian saw it late. Too late. In it went. The Antonio Conte era was off to a flyer. And so was he.
Down the touchline he ran, high-fiving a row of outstretched hands. This is why the foreign coaches come. It’s not just the money. It’s the Premier League. Not the best, not the classiest - but there really is nothing like it.
Should Costa have even been on the field? Well, that’s another story. Booked in the first half for dissent, he should have received a second yellow for a late lunge on Adrian with 25 minutes to go.
Anthony Taylor, the referee who had seemed so strict in the first half, ducked it. It’s all well and good giving referees protection, but players need it, too.
Ultimately the best team won, and Conte will be impressed with his team’s resolve. More worrying is that it took one West Ham attack to break them down. In the 77th minute, West Ham won a free-kick and, from it, a corner. And Chelsea cracked.
They had looked so comfortable, too. In control, West Ham at arm’s length. True, it had needed an horrendous mistake from Michail Antonio and a penalty to give them the lead, but Chelsea were good for it. If there was to be a second goal in the game, it was going to the boys in blue.
And then Dimitri Payet came on, and changed the dynamic. Suddenly, Chelsea looked less assured, vulnerable again, much like last season. West Ham won a free-kick, then another.
The second was in Payet’s range. Stamford Bridge, for the first time, seemed subdued. He hit the wall, to a relieved cheer, but the ball went out for a corner. And, from there, calamity befell Conte’s men.
Payet, who else, took the corner which was met by Collins. His glancing header may have struck Azpilicueta’s arm but as several West Ham players appealed, Enner Valencia continued playing and clipped the ball back to Collins.
He shot, first time, past Thibaut Courtois, whose first touch of the game may well have involved picking it out. Collins celebrated deliriously, the travelling fans serenaded the ‘Ginger Pele’. Someone will have to explain it all to Conte later, when he has calmed down. They may have to explain that this is fairly standard for the Premier League too, because for a manager used to the order of Serie A, it will take some getting used to.
Good grief, it was frantic in the first half. A game of few chances but plenty of fury, and more than a few yellow cards.
No doubt emboldened by the Premier League’s new guidelines, referee Taylor took few prisoners, much like the teams. The match was just three minutes in when Chelsea’s new signing - there have been considerably fewer of them than many imagined - N’Golo Kante hacked down Andy Carroll inside the West Ham half.
Usually, English referees take the first one as a loosener and issue the instruction not to do it again. Taylor produced a yellow card instead. Kante looked mystified. Could it be that we will be playing something akin to the rules of football in England this season? That will take some getting used to.
If so, someone is going to have to get the message through to Diego Costa, and quick. Chelsea’s striker could spend more time suspended than a circus trapeze act if not.
In the 19th minute, Oscar dispossessed Mark Noble, turned and ran on goal. He passed Winston Reid on the outside and there was undoubtedly contact, but it was minimal and barely impeded his run. Oscar fell, dramatically. A bit soft. Taylor was having none of it.
On the touchline, Antonio Conte hopped around like a live prawn on a hot plate. Costa chased 40 yards down the pitch to berate Taylor in person. Big mistake. There is zero tolerance of dissent this season and he became the second name in the book. Third was James Collins for kicking Costa, something several of his team-mates may feel like doing this season if he does not learn to keep his mouth shut.
West Ham were scrappy and tenacious but, without Dimitri Payet in the starting line-up and losing new signing Andre Ayew to a right leg injury after 34 minutes, posed little threat to the Chelsea goal early on. Chelsea had the best of the chances, but could not find a way through.
In the 12th minute, a delightful backheel from Oscar found Branislav Ivanovic on the overlap - unsurprisingly rid of the sluggishness that seemed to have affect him at the start of last season.
The Serb cut inside Cheikhou Kouyate and hit a snap shot, low and at the near post, needing goalkeeper Adrian to have his wits about him to keep it out.
Eden Hazard, another disappointing performer this time last season, hit a shot from 20 yards that flew over the bar after 14 minutes - a recklessness replicated by Costa shortly before half-time when put in by Hazard.
It remains to be seen how Hazard responds to his role under Conte, which would appear to involve staying wider for longer than he did under Jose Mourinho. It meant he posed little threat to goal, unless making enormous ground, as he did most spectacularly after 31 minutes.
It was a fine run, the sort Hazard made frequently in Chelsea’s title-winning season, speeding down the flank before darting inside and striking a low shot, curled towards the inside of the far post, fractionally overhit.
It served as a warning that if Chelsea can recapture their form of two seasons again, they may make a mockery of that 10th-place finish in May. As if to underline that fact, with virtually the last kick of the first half Willian - industrious as ever - struck a free kick from 25 yards that was deftly flicked over by Adrian.
Slaven Bilic, West Ham’s manager, could be seen in conversation with Payet shortly before the second half began. Payet gave a thumbs-up signal to a figure in the crowd, but it was too late. Within a minute of the restart, Antonio had given away a dreadful penalty.
Two mistakes for the price of one. First, he gave the ball straight to Cesar Azpilicueta just outside the West Ham penalty area. Then, attempting to limit the damage, he went in on him clumsily and sent him tumbling to the ground.
No doubt in Taylor’s mind this time. Hazard stepped up and smashed his shot high and straight into the roof of the net.
Conte turned to the crowd, punched the air and roared with delight. Pep Guardiola’s reign started with a penalty too - with a competition this intense, it doesn’t pay to be choosy.
Daily Mail