Arsenal reached the Europa League semi-finals with a 6-3 aggregate win over CSKA Moscow despite a nervy 2-2 draw in Russia.
Arsene Wenger's side were trailing 2-0 and under pressure when Danny Welbeck's second-half goal gave them breathing space.
The hosts, who led through Fedor Chalov and Kirill Nababkin, went close to drawing level on aggregate and leading on away goals as Petr Cech saved Aleksandr Golovin's free-kick and Sergei Ignashevich shot narrowly wide.
Arsenal, the leading scorers in the competition, did not have an effort on target in the first 70 minutes, and Laurent Koscielny wasted a glorious chance before Welbeck struck.
Aaron Ramsey's goal in stoppage time made certain of their progress into the last four alongside Atletico Madrid, Marseille and Salzburg.
Viktor Goncharenko's men had dreamed of an upset when Chalov reacted before Shkodran Mustafi to score the opener after Cech saved Nabakin's header.
Cech was at fault when he could only parry Golovin's strike from 25 yards and Nababkin reacted first to double the hosts' lead.
But Arsenal, who lost midfielder Jack Wilshere to injury, kept their nerve to enter the semi-final draw, which takes place in Nyon, Switzerland, at 11:00 BST on Friday.
Arsenal avoid Barcelona repeat
Arsenal's Europa League dream lives on - just - after a tense night in Moscow, and Wenger can still hope for his first European trophy with the Gunners.
His side are in their first European semi-final in nine years, despite threatening to join Barcelona in the history books for all the wrong reasons.
Wenger, who made seven changes for Sunday's 3-2 Premier League win over Southampton with this game in mind, brought his rested big names in Mesut Ozil, Ramsey and Wilshere back into the starting XI against CSKA.
Despite stressing he was fully aware of the "warning" provided by Roma after they overturned a 4-1 first-leg deficit to reach the Champions League semi-finals at the expense of a stunned Barcelona on Tuesday, his team almost suffered the same fate.
With CSKA leading and asking some severe questions of the visitors, it required Welbeck - who scored twice against Southampton after what Wenger described as a "dark" time in his career - to save the day.
He latched on to a wonderful Mohamed Elneny pass to finish calmly 15 minutes from time.
That goal knocked the stuffing out of an impressive CSKA, who recovered well from losing influential Russia midfielder Alan Dzagoev to injury in the first half.
Ramsey, who needed treatment to a badly cut foot, showed similar cool when one on one with Igor Akinfeev with the local time past midnight.
In his post-game press conference Wenger was presented with a Russian hat, like the ones given as gifts to the Arsenal fans in the away end by CSKA.
It was a cordial end to a night which had threatened to be altogether more unpleasant for the Gunners.
Credit: The BBC