Kyogo Furuhashi fired home his 34th goal of the season to help Celtic complete a domestic treble with a 3-1 victory over Inverness Caledonian Thistle in the Scottish Cup final on Saturday.
The Samurai Blue forward was one of four Japanese players in Celtic manager Ange Postecoglou's starting lineup, along with Daizen Maeda, Reo Hatate and Tomoki Iwata.
The Hoops were slow to get rolling against their second-tier opponents but had clicked into gear by the time Furuhashi struck the opener in the 38th minute at Glasgow's Hampden Park.
Timing his run to perfection, the Scottish Premiership's most prolific scorer this season steered into the top right of the net with a precise first touch off Matt O'Riley's cross.
"Once Matt ran through, I knew exactly what would happen next...so I just ran there and he gave me the ball and it was a goal," Furuhashi told Celtic's official site.
Substitute Liel Abada made it 2-0 midway through the second half, with Inverness' Daniel MacKay pulling a goal back late before Neves Filipe sealed the result in the first minute of injury time.
The Scottish Cup victory, following Celtic's second straight Premiership and League Cup titles, completed a record eighth treble for the club.
"We worked hard every day, and this is the outcome of our hard work," Furuhashi said. "I cannot express in any other words other than it is unbelievable."
The trophy capped off an outstanding individual season for Furuhashi, who was named the Scottish Football Writers' Association Player of the Year in addition to the Scottish Premiership Player of the Year.
"It was a really happy and fulfilling season," said Furuhashi, who is back in the Japan squad for the upcoming June friendlies following his shock omission from last year's World Cup.
"I'm just grateful to be called up (for Japan). I want to repay it by getting results."
While Postecoglou has been linked with the managerial vacancy at English Premier League side Tottenham Hotspur, the former Yokohama F Marinos boss said his only thoughts were about Celtic's historic season.
"There will be a time to come for those kinds of questions but, for now, we've grasped a small chunk of history for ourselves and I'm not going to pass that by, by being sidetracked," Postecoglou told BBC.
Japan midfielder Daichi Kamada and former Samurai Blue captain Makoto Hasebe were on the losing side as Eintracht Frankfurt went down 2-0 in the German Cup final to holders Leipzig, who had second-half goals from Christopher Nkunku and Dominik Szoboszlai at Berlin's Olympiastadion.
The match was the final appearance in Frankfurt colors for Kamada, who is out of contract at the end of the season and has been linked with a move to Italian giants AC Milan.