Another Youssef El-Arabi goal was not enough to overturn a first-leg deficit as Arsenal reached the Europa League quarter-finals with a 3-2 aggregate win over Olympiakos
El-Arabi, whose extra-time winner in last season's competition dumped Arsenal out of the tournament, scored via a deflection six minutes after half-time to give the Greek side a 1-0 win on the night at the Emirates Stadium
Arsenal's defeat followed a poor second-half performance after a relatively untroubled opening 45 minutes where Mikel Arteta's side looked to consolidate their two-goal advantage in the tie, and should have added to it through Pierre-Emerick Aubameyang, who blasted over when well-placed
El-Arabi's finishing was also off when he fired straight at Bernd Leno before he found his shooting boots for the only goal of the night, to give Olympiakos realistic hope they could knock Arsenal out for a second straight year
But once Ousseynou Ba was sent off for two bookings within 10 seconds of one another, for fouling Gabriel Martinelli and then throwing the ball at him, their glimmer of hope faded, and Mikel Arteta's side survived a scare to reach the last eight
Arsenal named a strong team to see out a comfortable lead in the second leg of their last-16 tie and did just that before half-time, allowing Olympiakos plenty of the ball and remaining compact without it
They would have made life even easier for themselves had Nicolas Pepe's shot not deflected off Jose Sa, who had come a long way to meet him, and just wide of the near post
 A far easier chance for Aubameyang moments later was met with a less forgivable finish as the Gabon striker fired powerfully over from Dani Ceballos' through-ball when well-placed
Power was the aim for El-Arabi from Olympiakos' one real chance of the half, when a Sa goal kick caught the Arsenal defence flat-footed and only the forward's poor finishing, shooting straight at Leno, let them off the hook
That was the warning shot, but the second gave no reprieve
 Ceballos lost the ball well up-field six minutes after the break but with Arsenal committing numbers forward, Olympiakos sprung on the break
 Suddenly El-Arabi was found inside the box, and when Gabriel's deflection on his effort wrong-footed Leno, the Greek side had hope
Their play since the break had troubled the hosts and continued to do so, although with 13 minutes to go Martin Odegaard, on as a substitute, should have taken the pressure off Arsenal but after two goals in as many games, he fired well over when well-placed
Shortly before Ba's inexplicable red card, which left him in tears in the Arsenal tunnel knowing he had all-but ended his side's hopes of progressing, Aubameyang missed another glorious opportunity to seal victory, chipping Sa when clean through but missing the far post
Late on the restored Arsenal forward was twice more off target, but by now it mattered little
 The Gunners had done enough in Athens to progress, and were not punished for a poor performance on home soil
Arsenal boss "People take for granted that you play against any opponent and you're going to be through because of the name of the club they represent
 It's not like that
 Every team in Europe is really difficult to beat
"What we have to do, the way we are setup, the organisation we have and the way we want to play, we have to be much more efficient, much more simple, much more cohesive as a team
"Without that structure you are exposed when you lose the ball in really dangerous areas without any opposition
Arsenal's short trip to West Ham is live on this weekend, as part of  from 2
30pm; Kick-off at 3pm
The Europa League quarter-final and semi-final draw will be held on Friday at 12pm
 Follow live coverage across Sky Sports' digital platforms
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