Simona Halep thought another chance to win her first Grand Slam title "had gone" before she fought back to win the French Open.
Halep, 26, was a set and a break down against American 10th seed Sloane Stephens but won 3-6 6-4 6-1.
The Romanian had lost all three of her previous Grand Slam finals, including last year's Roland Garros showpiece.
"I felt 'it's gone, it's not going to happen again, but it's OK. I have just to play'," the world number one said.
Halep led by a set and a break in last year's defeat by unseeded Latvian Jelena Ostapenko, and said she used the experience of being on the wrong end of that fightback to help her turn around Saturday's match.
"When I started to win games, I said that last year the same thing happened to me," she said. "So I said there is a chance to come back and win it,
"I believed in that, and my game was more relaxed. I could make more things on court, and that's why I could win."
Halep rose to the top of the world rankings for the first time in October and has been the leading player on the WTA Tour this year.
But a first major title had eluded her until now, and she said she "could not breathe" as she closed in on it.
"I was very strong mentally to finish that," she said. "It's a special moment. I was dreaming for this moment since I started to play tennis.
"Roland Garros is my favourite Grand Slam. I always said that if I'm going to win one, I want it to be here."