Gentildonna survived a stewards' inquiry to see off Prix de l'Arc de Triomphe runner-up Orfevre and win the Japan Cup at Tokyo racecourse.
In a race featuring plenty of European interest, including the French-trained Arc winner Solemia, home-trained runners dominated the finish.
Orfevre was sent off favourite on the back of his effort in Paris, where he looked to have the race in the bag only to idle, wander around in the final few yards and lose out in the shadow of the post.
Yasutoshi Ikee's demonstrated no such tendencies this time though and was happy to settle in the pack under Kenichi Ikezoe as Beat Black set out to make all.
The early leader soon built up a healthy advantage and had five lengths in hand at the top of the straight but his early efforts began to tell in the final couple of furlongs.
Ikezoe was poised to challenge aboard Orfevre and when he gave the signal, the colt started to pick up and close the gap on Beat Black.
Gentildonna went with him though and finding himself a bit short of room between the two, Yasunari Iwata appeared to force his way out, bumping Orfevre in the process.
His mount, winner of the Japanese Fillies' Triple Crown this year, proved game in the finish and stuck her head out to edge out Orfevre by a nose at the line.
However, the stewards quickly called an inquiry, with trainer Sei Ishizaka enduring a nervous wait before his filly was finally confirmed the winner.
Rulership claimed third to give owners the Sunday Racing Co a memorable one-two-three, with Fenomeno also claiming fifth for the powerful team.
The Ed Dunlop-trained Red Cadeaux fared best of the European raiders in finishing eighth, although he did not enjoy the best of runs under Gerald Mosse.
Marco Botti's Melbourne Cup third Jakkalberry was 11th while the Luca Cumani-trained Mount Athos, who raced keenly early on, was 12th.
Solemia could finish only 13th for Carlos Laffon-Parias while Roger Varian's Sri Putra was last of the 17 runners.
Ishizaka is now considering sending Gentildonna overseas next season.
He said: "Although the Japan Cup was a big challenge for a three-year-old filly, I was confident that she was up to the competition and she proved that today.
"After her battle against tough competition in the Japan Cup, she will be turned out until her four-year-old season in which, depending on her condition, I will go on with my plan for overseas challenges, perhaps in Dubai, France or the USA.
"I am thinking long term, however, not necessary next year but even the year after that."
Laffon-Parias confirmed to the Japanese press that Solemia will now be retired.
He said: "It was a very good race.
"I think she did very well in regard to that she is coming off of a hard race in the Arc and her first overseas travel.
"It might have been different if she had had experience racing abroad and had more time to adapt to the fast track here.
"She will retire now."
"She will be turned out until her four-year-old season in which, depending on her condition, I will go on with my plan for overseas challenges, perhaps in Dubai, France or the USA" - Sei Ishizaka, trainer of Gentildonna
"It didn't really run fast enough for us but he's run a super race," said Dunlop's assistant, Robin Trevor-Jones.
"As you can see in the half last furlong there's another horse come across us.
"We should have finished sixth but we finished eighth. But he's run very well and we're proud of him.
"Now we'll get him ready for Hong Kong."
Botti's wife, Lucie, felt Jakkalberry might have been feeling the pinch following a tough outing in the Melbourne Cup.
She said: "His preparations all went as planned.
"He probably had a hard race in the Melbourne Cup and we're happy with how he raced today.
"We have no excuses with the outcome but there were very good horses in front of us today.
"He will get a break now and then we head for Dubai in February."
Mount Athos was unhinged by a stop-start gallop, according to Cumani's son, Matt.
"He ran OK but the pace was all wrong," he said.
"He didn't break well enough and when he couldn't get into a tactical position, he was at the mercy of the pace and it went slowly down right down the back side.
"And when they accelerated he found it hard to accelerate with them.
"We're happy with him but I think a longer distance is better for him."
Varian believes Sri Putra was running on empty.
He said: "He was positioned well, but had nothing left.
"He's probably more tired than we thought after a long season."