Wrapping up the title race with one match to spare, Celtic won their 52nd Scottish league championship with a squad featuring a distinctly Japanese flavor.
Japanese players Kyogo Furuhashi, Daizen Maeda, Reo Hatate and Yosuke Ideguchi were part of the Celtic outfit crowned champions Wednesday following a 1-1 draw with Dundee United that stretched the Glasgow club's unbeaten run to 31 consecutive games.
Former Yokohama F Marinos and Australia manager Ange Postecoglou brought in the Japanese quartet as he masterminded a Premiership and League Cup double in his first season at Celtic Park.
By winning the double in their debut season, the four followed in the footsteps of countryman Shunsuke Nakamura, who wore the famous green-and-white jersey from 2005 to 2009 and remains a fan favorite.
"They've been great," Postecoglou said. "Obviously for them it was a big challenge coming from the other side of the world, different country, different culture, and they've all been outstanding."
Postecoglou's credentials were never in question among J-League watchers who saw him lead a revitalized Marinos to the 2019 J1 crown, but the 56-year-old Australian was met with doubts and intense media scrutiny upon taking the reins of a Celtic club in turmoil last June.
Coming off a disastrous season in which they went without a trophy and lost a one-sided title race to their arch rivals, cross-city giants Rangers, the Hoops looked unprepared to mount a serious challenge.
Postecoglou signed Furuhashi from Vissel Kobe in one of his first transfer-market forays, raising eyebrows locally with a move that quickly proved to be a masterstroke.
Arriving at the start of the European season but midway through a J1 campaign in which he had been leading all scorers, the 1.70-meter forward became an overnight hero among the Celtic faithful.
Scoring in his first match, then hitting a hat-trick in his home debut, he went on to amass 18 goals across all competitions by the time Celtic sealed the league title, despite missing three-and-a-half months with a hamstring injury.
In December's Scottish League Cup final, he scored both goals in a 2-1 comeback against Hibernian that gave Postecoglou his first trophy as Celtic manager.
Furuhashi's success set high expectations for Postecoglou's former Marinos charge Maeda, Kawasaki Frontale talent Hatate and Gamba Osaka utility Ideguchi, who arrived together following an audacious January transfer window swoop.
The addition of three more Japanese players was headline material in both Britain and Japan, but Postecoglou resisted characterizing them by nationality.
"We have to be careful about just saying 'four Japanese players,'" the manager said during a January press conference. "These are four individuals, they are totally different people."
While Ideguchi appeared a handful of times off the bench, Maeda and Hatate made crucial contributions in the second half of the league campaign and became stars of the club.
Maeda netted on debut and has been one of the league's most prolific scorers since his arrival, while Celtic fans sang Hatate's name from the stands after his two-goal man-of-the-match performance in a 3-0 Old Firm derby win over Rangers in February.
"Obviously Kyogo made a massive impact for us, and for me, because he was kind of my first signing and it was important he was successful, and he was," Postecoglou said.
"And then Daizen, Yosuke, Reo all contributed. They've now won a championship in another country and I think they'll take great pride in that."
After energizing a storied club and raising expectations for future J-League transfers to Europe, Celtic's Japanese contingent will have a chance to perform under a bigger spotlight next season, with the Premiership win garnering a direct ticket to the UEFA Champions League group stage.
Postecoglou believes the club will be ready to make the step up.
"Well, we have to be. That's what we'll do," he said.