David Raya proved the hero as Arsenal survived a penalty shootout to scrape past Porto and reach the quarter-finals of the Champions League for the first time in 14 years after a tense last-16 duel had ended 1-1 on aggregate on Tuesday.
Porto, who won the opening leg 1-0, proved stubborn opposition for the Premier League leaders and Arsenal fans must have feared another night of European heartache.
But Martin Odegaard, Kai Havertz, Bukayo Saka and Declan Rice all tucked away their spot kicks with clinical precision and Arsenal keeper Raya made two saves.
He got the slightest of touches to send Wendell'seffort against the post and then saved Galeno's penalty to send Arsenal through 4-2 in the shootout and spark wild celebrations.
Leandro Trossard's goal shortly before halftime had levelled the tie but Arsenal struggled to break down a disciplined Porto side who produced a defensive masterclass.
Extra time failed to separate the sides but Mikel Arteta's team held their nerve to snap a run of seven successive exits at the last-16 stage. The last time they reached the quarter-finals in 2010 they also beat Porto in the last 16 and they will go into Friday's draw full of confidence that they can go further.
"For them to do it when the club hasn't done it for 14 years that tells you the difficulty," Arteta, whose side have won eight successive Premier League games to edge ahead of Manchester City and Liverpool, told reporters.
"They are willing to sacrifice anything to win.
It was hard on Porto who produced a classic away performance with 41-year-old defender Pepe a rock at the back and Evanilson twice going close to stunning the hosts.
But they were left deflated as their dreadful record away to English clubs continued with a 20th defeat from 24 games.

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