Chelsea's rousing final flourish sees off Watford but performance raises as many questions as it answers

And while Chelsea showed the resolve of champions, and Conte his tinker’s touch, it was really a performance that raised as many questions as it answered. After cancelling out Pedro’s early goal on the stroke of half-time, Watford tore into Chelsea after the break, trampling over their midfield and creating enough chances to put the match out of sight.

Manager Marco Silva will rue the two glaring misses by Richarlison at 2-1 up, that if converted might have snapped Chelsea’s resistance once and for all.

But the introduction of Batshuayi for the last 30 minutes, combined with a couple of nifty formation shifts, succeeded in turning the game back Chelsea’s way. Freed from their defensive responsibilities, the outstanding Pedro and another substitute in Willian were able to turn their lasers on the Watford defence. Cesar Azpilicueta was switched from the right flank to the left, from where he drifted in to head in the decisive goal, putting Chelsea 3-2 up.

Batshuayi may well have put the burners on his Chelsea career, too. This sparkling cameo was a reminder that he is still capable of being the £33 million striker that Chelsea signed last summer, as long as he is used correctly. Batshuayi with his back to goal is no good to anyone except the opposition. But given the licence to run at defences and spring the offside trap, he is a force. He can expect another run-out in the League Cup against Everton in midweek.

And yet the concerns over Chelsea’s defensive frailties will simply not go away. Conte may ultimately have won the day, but this is not the sort of football with which he made his name, probably even not the sort of football he wants to be playing. The combination of Cesc Fabregas and Tiemoue Bakayoko in midfield is currently conceding a goal every 38 minutes, and without N’Golo Kante, Conte will have been alarmed at the lack of cover they provided.

Marco Silva’s Watford, meanwhile, left Stamford Bridge empty-handed but with their reputations enhanced. They simply ran out of puff in the final 20 minutes, but by that stage their excellent collective pressing and intelligent passing moves had shown that they are well worth their place in the Premier League’s top six.

Silva also had a legitimate grumble about the corner from which Chelsea opened the scoring, arguing - correctly, as it turned out - that the ball had come last off Eden Hazard. But there was no arguing with Pedro’s finish, a brilliant curling shot that clattered in off the post from 25 yards.

For an hour, Pedro was having one of those games when he is less a component of a team and more a freak weather occurrence. There were stepovers, cheeky nutmegs, ambitious dribbles out of his own half. He shot from distance again and again. He raged at team-mates for playing the wrong pass, or playing the pass too slow, or occasionally simply just not being as good as Pedro. He made scything tackles that had no real function except to imprint his presence on the game like a tattoo.

Unfortunately, his team-mates were not quite on his level. Conte spread his arms, urging more width, more speed, more effort, more strength, more, more, more of everything. But Chelsea still struggled to get a grip on the game. And in the 120th of 120 seconds of injury time at the end of the first-half, In the 120th of 120 seconds of injury time, Watford hoisted in a long throw from the right. David Luiz’s header hit Bakayoko, and Abdoulaye Doucoure lashed the ball past Thibaut Courtois from a tight angle.

Watford carried on where they left off after the break. In the 48th, Richarlison missed an open goal after Kiko Femenia’s sumptuous cross from the right. In the 49th, Watford again broke with numbers, Roberto Pereyra squaring the ball to Richarlison, Richarlison squaring it back to Pereyra, and the ball buried past a helpless Courtois. In the 53th minute, Richarlison missed a free header from five yards. The second half was not 10 minutes old and Chelsea should really have been out of the game.

Conte was desperate. Batshuayi came on, but Watford were still haring down the flanks, to the extent that Pedro was sprinting towards his own goal to fill the vacant left-back position. Marcos Alonso made way for Willian soon after that, Conte going back to the 4-2-4 he favoured at the beginning of his managerial career. It had an instant effect. With 19 minutes remaining, Pedro found some space, whipped in a cross, and Batshuayi’s diagonal run to the near post was timed to perfection, his glancing header exquisite.

Following the goal, Conte went back to 3-4-3, Pedro tucking in at right wing-back. Batshuayi was still the liveliest player on the pitch: almost jamming one in from a narrowing angle, almost catching Gomes out with an early curler from distance. And in the 87th minute, Chelsea completed their escape.

Willian ghosted too easily around Ben Watson and crossed from the right. Christian Kabasele - who had earlier missed two free headers - flicked the ball just out of the reach of Batshuayi, but arriving at the back post was Azpilicueta. Azpilicueta only needed to get his header on target, and did. Conte spread his arms and collapsed into the crowd in relief.

In the final minute of injury time, Miguel Britos tried to dink the ball out of defence, a bold move even if it were not the final minute of injury time and your name were not Miguel Britos. Bakayoko intercepted, and a few seconds later the ball was in the back of the Watford net, Batshuayi latching onto it and nestling the ball past Gomes.

“That’s why we’re champions,” the home crowd sang in the final minutes. Well, fair enough. But for much of the game, they had shown us why they might not be for much longer.