It was the biggest moment of Giorgos Giakoumakis' burgeoning career, scoring an iconic winner in one of Europe's most febrile derbies, yet the striker came to regard it as a "curse".
The forward propelled AEK Athens towards the Greek title four years ago with a decisive injury-time strike at Olympiakos.
It marked Giakoumakis' first league goal for the Greek giants, but also proved to be his last as the dream move curdled.
Having since rebooted his fortunes with a remarkable season in the Netherlands, the Greece international has overcome early doubts at Celtic by playing a pivotal role as the club home in on the title.
BBC Scotland delves into the 27-year-old's backstory and examines how the striker who once struggled for goals has become a poacher supreme.
Derby heroics a rare AEK highlight
Giakoumakis was never a prolific scorer in his homeland, where his total amounts to 23 goals in 138 games. Starting out with Platanias on his native island of Crete, he took three seasons and 22 matches - mostly as substitute - to open his league account.
His most fruitful season - a haul of 11 in 26 games in 2016-17 - was suitably impressive to catch the eye of AEK Athens.
It was a marked step up in quality, expectation, and pressure at a complicated powerhouse where Giakoumakis found patience - and opportunities to prove himself - in short supply.
His momentous derby goal in February 2018 - as AEK went on to win their first title in 24 years - was a rare personal triumph. Thrown on as a late substitute at 1-1, Giakoumakis burst between two defenders to meet a 94th-minute cross with a clinical first-time shot, a finish that has become his hallmark at Celtic.
It remains an iconic strike in AEK Athens' history, yet Giakoumakis later remarked: "I would have preferred to have scored 50 goals with AEK and not the one against Olympiakos. After that a curse followed me, everything went wrong."
Within 18 months of his arrival, Giakoumakis was sent out on loan and his AEK hopes were all but over. By the time of his permanent departure in summer 2020 he had made just nine starts across 48 appearances, scoring three times. So did he have justifiable grievances over such meagre game time?
"Giakoumakis said AEK didn't believe in him and he didn't give him the opportunity to show his quality because he came from an average team like Platanias," says Greek football journalist Nikos Toskitsis.
"He had a lot of pressure on him from the start and AEK did not have time to wait for him to deliver.
"An important problem was the instability of AEK. It was a difficult time for the club, they frequently changed coaches and were not happy because they were not having much success."
Redemption in Eredivisie 'paradise'
Giakoumakis sought an escape and found it in an Eredivisie relegation battle. After loan spells with OFI Crete and Polish side Gornik Zabrze, it was modest Dutch club VVV Venlo who took a chance with a permanent move for the striker in summer 2020.
The man who made the deal happen, Venlo sporting director Stan Valckx, looked beyond the bare statistics to unearth a rough diamond.
"Giorgos did not have an outstanding CV," says former Netherlands international Valckx. "But there is more to him. With his mentality, spirit and finishing, I saw enough to know he could be a good weapon for us."
Having travelled to Poland to see the striker in action and discuss a move, Valckx's plans hit a snag when Covid restrictions saw him locked out of the game and forced to watch on TV in a local cafe.
"Giorgis got a knock on the head just before half-time so I thought we wouldn't see him the next morning for our meeting," he adds. "It was remarkable he showed up - the blood was still seeping from his head. That showed his character and determination.
"I was surprised he knew all about the Venlo players. He came for less money than he was earning at Zobrik and AEK Athens. He was prepared to take a step back to move his career forward."
What happened next was beyond Valckx's wildest expectations. Giakoumakis crowned his debut with a hat-trick in a 5-3 win and the goals kept coming at an astonishing rate.
He scored four in a match - twice - and ended the season as the division's top scorer by a seven-goal margin with 26 in 30 games.
Even more startling was that Giakoumakis' scoring feats came in a struggling side. Six games in, Venlo were annihilated 13-0 at home by Ajax, and they ultimately were relegated.
Having been stymied by the regimented defensive style of Greek football, Giakoumakis had found redemption and freedom in the Eredivisie. His 6ft 1in frame provides an aerial prowess, but he scored all kinds of goals and displayed an unstinting work ethic.
"Venlo was the right club at the right time for him," says Valckx. "But also the Eredivisie is a paradise for strikers, wingers, young players. You see many players thrive who were maybe not successful in other countries.
"In Venlo we have to defend 60-70% so mostly our strikers are in our own half. That makes it even more remarkable that he scored that many goals.
"He is a hard worker and a great team-mate because he never gives up. Even if he has barely touched the ball for 85 minutes, he still believes he can score."
Casting off injury woes to power Celtic title bid
Suddenly Giakoumakis was a sought-after commodity, and Celtic pipped Werder Bremen to his signing on the final day of last summer's transfer window with a £2.5m fee and four-year contract.
Fans eager to see if the Greek could replicate his prolific Eredivisie exploits soon had their expectations tempered. Giakoumakis arrived with a shoulder problem and injuries blighted his opening months. By the winter break he had one goal, two starts and eight appearances.
When Giakoumakis rolled a feeble penalty into the grasp of Max Stryjek to cap a frustrating 0-0 home draw with Livingston in late October, it amplified his early struggles.
Determined to prove himself, the striker sacrificed days off during the winter shutdown and poured himself into recovering from a knee injury. Come the new year, the extra graft reaped rewards as a refreshed Giakoumakis emerged looking a different player.
With Kyogo Furuhashi missing the opening three months of 2022, the Greek took on the striking mantle. He netted 12 in 17 games, including a hat-trick in successive home league matches, as Celtic powered from six points behind Rangers to their current six-point lead.
His 12 goals from his first 12 starts is the joint best record, alongside Tommy Johnson, of any Celtic player in the past quarter century. Of his total haul of 13 Celtic goals, the first dozen were all first-time finishes.
Having looked out of sync with Celtic's high-tempo style earlier in the campaign, Giakoumakis has come to embody the relentless work ethic Ange Postecoglou demands. He leads the press, and his tireless running and physicality were notably missed when injury kept him out of last month's Scottish Cup semi-final and Celtic fell to a 2-1 defeat to Rangers.
With Celtic set to reclaim the title, it will fulfil the striker's bullish prediction from February. Giakoumakis has backed up his big talk and Postecoglou believes there is plenty more to come from his late-blooming striker.
"It has worked out well for him," said the Celtic manager. "He had a disrupted time in the first few years. Sometimes when that happens it just means that they blossom a bit later. Hopefully his best years are well ahead of him."
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