Time was running out for Heimir Hallgrímsson’s men to salvage their WC qualifying campaign against a Portugal team that was one win away from booking their plane ticket across the Atlantic.
The visitors began confidently, with Cristiano Ronaldo having a few early chances to break the deadlock, but it was the hosts who struck first.
Troy Parrott headed home from point-blank range after Liam Scales nodded Jack Taylor’s searching corner back across the box, and the Aviva Stadium erupted into raptures.
The Boys in Green were inches away from scoring a second when Chiedozie Ogbene’s brilliant angled effort cannoned off the post.
However, after Diogo Dalot and Joao Felix spurned chances to restore parity, Parrott incredibly doubled Ireland’s lead in first-half stoppage time with a superbly taken close-range finish to stun Roberto Martinez’s side.
Hallgrimsson’s team were showing admirable defensive discipline, but Vitinha should have done better after scuffing his finish at the far post from Bernardo Silva’s corner shortly after the restart.
Portugal’s hopes of a comeback took a huge hit just past the hour mark when Ronaldo was shown a straight red card following a VAR review for lashing out at Dara O'Shea.
The five-time Ballon d’Or winner sarcastically applauded the crowd as he departed, leaving his side with a mountain to climb heading into the final third of the match.
Ogbene looked to rub salt into the visitors’ wounds when he flashed an effort wide, but Irish chances were few and far between.
There was no need for the hosts to be needlessly expansive, despite their one-man advantage, particularly given how rarely Caoimhin Kelleher had been tested by Portugal’s uncharacteristically blunt attack.
The hosts carefully orchestrated their own breaks forward, as the tireless Ogbene teed up Finn Azaz, who saw his effort deflected wide.
Ultimately, Parrott’s brace proved to be the difference in what is surely one of the finest results in the Republic of Ireland’s recent history.
A WC qualifying campaign, which began so disappointingly, now has the chance to give the Boys in Green their first appearance on football’s biggest stage since 2002.
Victory away at Hungary on Sunday will get the job done, while Portugal will fancy themselves to finish their quest at home to Armenia.
Flashscore Man of the Match: Troy Parrott (Republic of Ireland)
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