Belle d'Or got up in the shadows of the post to land the Listed Coral Distaff at Sandown Park on Saturday.
The three-year-old needed every yard of the mile trip and it looked like John Gosden's filly was going to have to settle for second place behind long time leader Wee Jean as the field entered the final furlong.
However, jockey William Buick managed to galvanise the 11/2 shot for one last effort as the pair lunged for the post and she just managed to get her head in front, landing the Listed event by a nose.
Buick said: "We went very steady and quickened up, I knew what was going to happen but I nursed her into it and she came good at the end.
"I'm just pleased she got her head in front. I thought she'd won."
Gosden said: "It was only her third race and she was a little green at the bottom of the straight. When Hughesie quickened you could see her thinking 'what am I meant to do?'.
"She changed her legs inside the last furlong and galloped out well.
"William said to stay at a mile for now, that's fantastic to win a Listed and we'll have to look at taking her elders on now."
The 5/4 favourite Queen Catrine put in a laboured effort under Ryan Moore and couldn't land a blow, eventually finishing unplaced.