There is a graffiti mural in the north stand – home to the most ardent, impassioned Olympiakos ­supporters – that displays a mockup of ­Muhammad Ali standing over his opponent sandwiched between the words: “Piraeus means knock out!”

And so it proved for Aston Villa, whose European adventure came to a joyless end in the Greek port. A familiar face landed the killer blows, Ayoub El Kaabi scoring his fourth and fifth goals of the tie to earn a 6-2 aggregate win.

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Unai Emery, a four-time Europa League winner, will not add the Europa Conference League to his honours list this season and Villa’s hopes of a first major trophy since 1996, and first on the continent since lifting the ­European Cup in Rotterdam in 1982, are over.

Villa can soothe the stinging ­disappointment by qualifying for the Champions League as early as Saturday – if Tottenham fail to beat Burnley – or Monday if they beat Liverpool. “We have to be a little bit frustrated, a little disappointed but react quick in our mind for ­Monday,” Emery said. “Congratulations to Olympiakos. It is a difficult day but we have to quickly shift.”

There were a few episodes ­symptomatic of a painful night for Villa, who never truly looked like overturning the two-goal deficit from a damaging first-leg defeat. Their so-often fruitful high line came unstuck when a VAR review deemed El Kaabi onside as Olympiakos doubled their lead on the night in the 78th minute, firing in from close range.

Lucas Digne sent a cross straight down the throat of the Olympiakos goalkeeper Kostas Tzolakis at 1-0 down. Earlier in the second half the fit-again Emiliano Martínez and Douglas Luiz pushed simple passes straight out of play.

Emery had raised the potential scenario of Villa conceding when discussing the psychology around the tie, stressing they would need to keep their counsel and retain confidence in the gameplan, but knew doing so made a tough task at the outset considerably harder. Villa will be delighted to see the back of El Kaabi, who built on his hat-trick at Villa Park by opening the scoring after 10 minutes here. Daniel Podence hovered on the ball, waited, and then rolled a pass into the overlapping Olympiakos left-back Quini, who sent a low cross into the area, which El Kaabi, who spent last season playing in Qatar, converted off-balance to register his 31st goal in 46 appearances this season. Martínez, back from a thigh injury, dashed across his goal but the ball was already in the Villa net.

“The tie was unfortunately lost in the first leg – we didn’t control the game or manage it well enough, the performance was poor,” said the Villa captain, John McGinn. “For us going into [another] European competition next season we need to learn how to manage moments a lot better. Of course we wanted to do better this year and get to a European final but we will do everything we can to get ourselves back into this position and get to a final.”

For Villa, El Kaabi’s strike was a leg-up that only further empowered Olympiakos and Emery could only preach calm to his players in a febrile atmosphere for so long. Villa were booed by a vociferous home support the moment they emerged for the warmup and their every touch was jeered. When Villa’s starting lineup was read aloud 10 minutes before kick-off, the stadium announcer’s words were indistinguishable, drowned by the deafening noise.

Villa saw plenty of the ball but more often than not they were faced with nine red-and-white striped shirts and the goalkeeper Tzolakis behind the ball. Ollie Watkins forced Tzolakis to push over a flying header in second-half stoppage time but otherwise there were few clear-cut chances. Leon Bailey tested Tzolakis with a rasping drive from distance that­ ­skidded off the right boot of an Olympiakos defender, forcing the goalkeeper to paw his left-foot strike over.

Emery had limited options on the bench, with the centre-back Clément Lenglet the only outfield substitute over the age of 21. The Villa manager introduced Jhon Durán before the hour mark and the midfielder Tim Iroegbunam midway through the second half in place of defender Diego Carlos but by then it was ­impossible to escape the sense they had left themselves to much to do.

Iroegbunam’s first touch was to cannon a pass meant for Bailey out of play. Durán blasted a shot straight at Tzolakis and Watkins sent a header on to the roof of the net.

Santiago Hezze, who also scored in the first leg, missed a chance to kill the game but El Kaabi was more ­ruthless, rampaging through on goal and leathering in past Martínez to register his second of the game.

With the game dead, Emery ­introduced three teenagers, ­including a debut for the 19-year-old defender Finley Munroe.

McGinn hastily choreographed ­Villa’s players off the pitch in ­anticipation of the wild celebrations, capped by a communal singalong. “Dear Aston Villa fans, please remain seated at the end of the match,” the stadium announcer said ­approaching the final whistle. There was little chance of much else after this.

Olympiakos can look forward to a first European final after becoming the first Greek team to reach such a stage since arch-rivals ­Panathinaikos in 1971. Their manager, José Luis Mendilibar, was applauded by local journalists as he walked into his post-match press conference.