Enable regained her King George VI And Queen Elizabeth Qipco Stakes crown after a titanic tussle with old rival Crystal Ocean at Ascot.
Frankie Dettori had to bide his time in midfield as Aidan O'Brien's four-strong challenge made the pace in the mile-and-a-half Group One.
But as O'Brien's Derby winner Anthony Van Dyck faded out of contention, the race culminated in a hard-fought head-to-head between Enable and Crystal Ocean in the final two furlongs.
Enable, winning her 11th successive race and ninth at the highest level, eventually came out on top for Dettori and trainer John Gosden - delivering by a neck as the 8-15 favourite, with French challenger Waldgeist a length and three-quarters further back in third.
Dettori told ITV Racing: "What a fight we had - I'm exhausted too, emotionally as well.
"From a furlong and a half out it was gloves off, let's have a scrap. She's good, but she's also very brave.
"I'm lost for words."
Gosden said: "She's everything you ever want. The draw rather affected her, she was suddenly very wide, so Frankie dropped back further than he wanted.
"She's a brave and wonderful filly, and what a great battle with Crystal Ocean.
"It's what you wanted to see."