With most of the pre-match talk centred on the omission of Cristiano Ronaldo, Portugal allayed any fears of disharmony with a breakthrough inside the opening quarter-hour.
Having struck the post just moments before, Goncalo Ramos combined brilliantly with Joao Cancelo as the full-back broke through the hosts’ defence and finished coolly past Mads Hermansen.
Despite that setback, Denmark restored parity in the 23rd minute, as Joakim Maehle’s cut-back in the box was superbly curled into the far corner by Mikel Damsgaard.
Victorious in five of their last seven away matches (D1, L1), the Selecao regained the lead just three minutes later, with Bruno Fernandes assisting Ramos for a confident low finish beyond Hermansen.
That was the Milan striker’s second international goal in the space of four days, repaying the faith shown by new boss Jorge Jesus.
Determined to press home their advantage, Portugal went close to a third before half-time, as Nuno Mendes fired wide and Ramos saw a close-range effort repelled by Hermansen.
Denmark started the second period on the front foot, and Brian Riemer’s men were duly rewarded with a second equaliser of the night in the 53rd minute. Damsgaard was the architect as he released Rasmus Hojlund, who held his nerve to lift a sumptuous finish over the onrushing Diogo Costa, before pulling out Ronaldo’s trademark celebration.
That sparked the visitors into life at the other end, as the lively Ramos powered a promising chance over, while Ruben Neves saw a low strike thwarted by Hermansen.
Undeterred by those missed opportunities, Portugal were soon celebrating their third goal in the 67th minute, with Vitinha rising highest in the box to convert from a trademark Fernandes delivery.
Having already relinquished the lead twice, the visitors looked to control the closing stages, as Jesus turned to Joao Neves and Joao Felix on his bench.
And it was the latter who put the seal on a superb victory for the Selecao, sweeping home a clinical finish from Diogo Dalot’s pass, as Portugal cemented their place at the top of Group A4 with a third win from three matches.