England came into this knockout fixture on the back of three consecutive 2-0 victories, while contrastingly, Portugal needed to haul themselves from the foot of Group A with an 89th-minute winner in their final group game.
Nonetheless, both sides looked well-matched after 30 minutes, with a shot on target apiece.
The Esperancas were the first to draw a save when James Trafford got down low at his near post to deny Pedro Neto, before Celton Biai held Anthony Gordon’s effort from a tight angle at the other end.
With little to separate the teams, a piece of incisive play from the Young Lions made the difference in the first half as Noni Madueke played in Morgan Gibbs-White, who pulled back for Gordon to sweep home.
Although a slender lead at the break, seven of the previous eight head-to-head encounters had been won by the side who had opened the scoring, a fact the Portuguese seemed to be aware of as they emerged with renewed vigour.
England survived a nervy passage of play when a couple of failed clearances eventually saw Trafford gather the ball, but Rui Jorge’s side were certainly on the front foot as they searched for an equaliser.
With under 20 minutes to play, a dangerous whipped ball for Henrique Araujo led to a tangle in the area, but after a VAR review, referee Rade Obrenović upheld his decision to give a free-kick England’s way.
The substitute was in the thick of it moments later when his header struck the crossbar, but Portugal remained undeterred as the pressure ramped up.
Despite relentless Portuguese attacks, England ultimately dug deep to keep the Iberians at bay, seeing out the contest to send three-time finalists Portugal home without a clean sheet to their name in an ultimately underwhelming campaign.
Lee Carsley’s side can now look forward to a semi-final match-up against surprise package Israel with one eye on a first U21 European trophy since 1984.
Flashscore Man of the Match: Taylor Harwood-Bellis (England)