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Chelsea was in total control from the off at The Valley, but was frustrated by Charlton in the first half, with Jamie Gittens and Josh Acheampong forcing Will Mannion into smart saves from range.

But Charlton's defence was breached in the fourth minute of stoppage-time at the end of the first period when Jorrel Hato volleyed his first Chelsea goal into the roof of the net after a miscued header from Guiu.

Five minutes after the break, Chelsea added its second, with Tosin Adarabioyo's glancing header from Facundo Buonanotte's free-kick giving Mannion no chance.

Charlton dragged itself back into the match seven minutes later when Miles Leaburn was on hand to fire in the rebound of Lloyd Jones' saved header.

Guiu took just five minutes to put Chelsea two goals ahead once more in similar fashion. He drilled his low shot past Mannion, who had got down well to smother Buonanotte's attempt.

The visitors' pressure finally told again in the 91st minute, with Pedro Neto picking out the bottom-left corner with a composed finish.

But it was substitute Enzo Fernandez – having twice forced Mannion into fine saves – who rounded off the scoring from the spot with the last kick of the game after the goalkeeper had brought down Estevao.

Not since August 2016, when Antonio Conte stepped into the dugout, had a Chelsea boss made a winning start at the club, with Rosenior bucking that trend.