Kai Havertz came off the bench and scored a 91st-minute winner as Arsenal clinched a 1-0 victory over Sporting in the first leg of their Champions League quarter-final in Lisbon.
Just when it seemed a cagey game was heading for a stalemate, Havertz produced a brilliantly composed finish from fellow substitute Gabriel Martinelli's pass to give Arsenal a potentially crucial advantage ahead of next week's second leg.
The Gunners were indebted to David Raya for keeping the scores level before that, with the goalkeeper having superbly tipped a Maxi Araujo shot onto the crossbar early in the game before making vital saves from Geny Catamo and Luis Suarez late on.
Arsenal had a Martin Zubimendi goal ruled out by VAR for an offside against Viktor Gyokeres but created few other chances before Havertz's late strike clinched a classic European away win which included another show of defensive resilience.
The result ensures a positive response to their consecutive domestic cup losses against Manchester City and Southampton and puts Arsenal on course to reach back-to-back Champions League semi-finals for the first time in the club's history.
In addition to Raya's outstanding performance in goal and Havertz's coolly taken winner, there was a historic landmark for Max Dowman.
At 16 years and 97 days old, the Arsenal substitute became the youngest English player in Champions League knockout history. He is second-youngest overall behind Bayern Munich's Filip Pavic.
Arsenal now turn their attention back to their Premier League title charge as they prepare to face Bournemouth in Saturday's early kick-off before the second leg against Sporting next Wednesday.
The winner of the quarter-final tie will face either Barcelona or Atletico Madrid in the Champions League last four.
Havertz's goal clinched the victory but only thanks to the heroics of Arsenal's goalkeeper beforehand. Raya's performance, in an outstanding season, further strengthens his argument to be considered the world's best goalkeeper.
That's certainly the view of his match-winning team-mate. "Unbelievable," Havertz told Amazon Prime. "He is still underestimated in the world of football but for me, the last two seasons, the best keeper in the world."
Raya showed outstanding reflexes to push Araujo's ferocious effort onto the bar early on. His near-post save from Catamo was similarly impressive and so too was his bravery in diving at the feet of Suarez soon after that, having kept out Catamo for a second time.
The statistics back up Havertz's view of his goalkeeper, certainly on the European stage. Since the start of last season in the Champions League, he has conceded only 12 goals from shots on target with an xG of 21.07, according to Opta.
In other words, he has prevented just over nine goals thanks to the quality of his saves. To put that in context, the next-highest total among goalkeepers in the competition in that timeframe is 6.12 from Real Madrid's Thibaut Courtois. Even he can't get close.
"At the moment he's phenomenal," added Arteta. "He has been extraordinary since he joined us. We are very lucky to have him."
Arsenal boss Mikel Arteta to Amazon Prime:
"Very happy to win away from home in the quarter-finals of the Champions League against a team that have not lost at home for I don't know how long. I think the last time was probably in Europe as well, that shows the difficulty of it.
"When we got into the final third and we sat there, we missed the final bit. We had to be a little bit crisper, faster, more efficient to break them down when they had that block.
"We had a goal disallowed and there were two or three occasions where we were close but we lacked that final pass. In the end a magic moment from the finishers wins us the game.
"Beautiful and that's the impact you need when you get to this stage of the season. Everybody has to make an impact and they certainly did that tonight."
