Ryan Moore played a major part in Gentildonna's historic Japan Cup victory as she became the first horse to win the Tokyo feature twice.
The English rider was on board Sei Ishizaka's filly for the very first time, as Yasunari Iwata had been in the saddle when she took a rough renewal 12 months earlier.
There was no luck for the three European raiders - Dunaden fared best to be fifth - but Moore was at the very top of his game in a race he wanted to win as he drove her past the line a nose ahead of the fast-finishing Denim And Ruby.
Gentildonna had finished second to St Nicholas Abbey in Dubai's Sheema Classic last March and was always in a prominent position, with Moore taking a commanding position with a furlong remaining but having to hold on desperately at the finish with rivals appearing from right across the track.
"Gentildonna has never run a bad race," said Moore.
"Unfortunately the race went very slow, and I had to let her take me into it. We were a little more forward than I had originally planned to have been.
"When we started racing from the 800 (metre-mark) she picked up very well to get to the front by the furlong marker. She's just so honest, and being a top horse she just kept giving that little bit more and just had enough."
Willie Mullins' Simenon, the Gold Cup runner-up who was fourth in the Melbourne Cup, could only manage 13th under Richard Hughes.
"I was surprised how slow it appeared to be early on," said Mullins.
"We thought it would be faster, but that's racing. I learned a lot and hopefully we'll be back with the same horse, or with a better one."
Ed Dunlop's Joshua Tree raced prominently for Johnny Murtagh but faded to eventually trail home last.
Dunlop said: "I think he got upset with all that razzmatazz and the build-up before the start.
"Johnny said that he lost the plot before the race and didn't want to run in the race. It's fantastic though, Gentildonna winning twice in a row, and we'll be back."