This was the kind of Premier League match you could happily watch all weekend: two sides sticking to the ultra-attacking principles of their managers and never afraid to take a risk.

In the end, a dramatic winner in the sixth minute of injury time from Spurs substitute Brennan Johnson, set up by the returning Son Heung-min, broke Brighton’s hearts in the cruellest fashion moments after they had come within inches of snatching the points themselves.

Related: Ivan Toney on target again as struggling Brentford stun toothless Wolves

It was a harsh lesson for Roberto De Zerbi’s assistant Andrea Maldera– the son of a former Milan defender – who watched his side take the lead after a penalty from Pascal Gross only for the impressive Pape Matar Sarr to equalise with his third league goal of the season on his return from the Africa Cup of Nations.

But for Ange Postecoglou, this was another famous comeback victory that moved Tottenham back into the top four and underlined the fighting qualities that have helped them pick up eight points with goals scored in second-half added time.

“All my teams historically have done that because the clock shouldn’t dictate the way you play,” said Postecoglou. “You should always be looking for goals, even if you’re losing 1-0 or winning 1-0. I think it helps you in games like this when you are chasing the game.”

Maldera had said De Zerbi was “not happy” with missing the match after having what Brighton described as “very invasive” dental surgery in Italy this week. Leading 1-0 but under siege from Tottenham 15 minutes into the second half, the Brighton assistant opted to make an attacking change by bringing on forward Ansu Fati for midfielder Adam Lallana rather than stick with what he already had. The result was a narrow defeat but you could only credit the visitors for their daring.

“We knew that we would have chances in the second half and that’s why we put on an extra forward,” said Maldera, who confirmed he had made the substitution on De Zerbi’s advice after speaking to him at half-time. “We always want to score the second goal – we don’t think about staying in our half.”

The previous meeting between these two sides six weeks ago saw Brighton race into a 4-0 lead and they were quickest out of the blocks once again here. Micky van de Ven was caught in possession inside the first 30 seconds and it required a full-stretch save from Guglielmo Vicario to tip Danny Welbeck’s shot wide. It was another mistake from the Dutchman after a misplaced pass from Destiny Udogie that gifted Gross the opportunity to score from the spot, which he accepted gratefully.

Falling behind was the prompt for Tottenham to finally wake up and a sumptuous through ball with the outside of his boot from James Maddison almost provided the equaliser but Jason Steele was equal to his shot.

The England midfielder then took aim himself after Brighton lost the ball in a dangerous area and was just inches wide of the far post. Exciting as Postecoglou’s team are in attack, however, a defensive lapse is never far away with this Tottenham team and Rodrigo Bentancur was next to oblige when he was dispossessed on the edge of his own area and Vicario came to his rescue to deny Kaoru Mitoma on his comeback from Asian Cup duty.

Richarlison looked wonderfully assured in his central role and the Brazilian set up Dejan Kulusevski for a chance that was quickly smothered by Steele. But he was culpable of delaying a pass to Maddison when Spurs found themselves through on goal just before the stroke of half-time.

Postecoglou had found himself in a similar position at half-time against Brentford at the end of last month before his side came out and scored three goals in eight minutes to seal victory. But despite Maddison testing Steele from a free kick early on, Brighton were not so obliging.

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Maldera decided to gamble with Fati but it backfired almost immediately when Sarr burst into the box and saw his initial cross defected on to a post by Lewis Dunk, only for the Senegal midfielder to bury the rebound from a tight angle. That was the moment for Son to make his long-awaited return as Postecoglou took his opportunity to roll the dice with a triple substitution.

But their best chance seemed to have been and gone when Johnson could only direct his shot straight at Steele as Brighton weathered the storm after the equaliser. They had chances to snatch all three points when Welbeck stabbed his effort just wide before substitute Benicio Baker-Boaitey saw his shot whistle past a post as Postecoglou watched on impassively.

The match-winning moment arrived 30 seconds later when Johnson touched home Son’s cross at the far post to lift the roof off and leave Brighton cursing their luck.