Jelena Ostapenko said she was amazed to be the first unseeded player since 1933 to capture the French Open on Saturday in a stunning and fearless 4-6, 6-4, 6-3 win over Simona Halep.
"I can't believe I am the French Open champion at just 20. It's amazing," said Ostapenko, the first Latvian to claim a Grand Slam crown.
It was also her first career title in just her eighth Slam appearance and will see her world ranking rocket to 12 from 47.
Ostapenko fired 54 winners and 54 unforced errors compared to Halep's eight and 10 respectively.
"I knew about the history," said Ostapenko.
"I knew that Gustavo Kuerten also won his first title here also in 1997 (the year she was born)."
"There are no words. It's just amazing. It was my dream as a child to win Roland Garros."
She was 3-1 down in the second and third sets but kept coming back with her no-fear hitting.
"I knew Simona was a great player. But I tried to play aggressive and everything turned my way. I fought for every point. I'm glad it finished my way," added the Latvian who finished the tournament with 299 winners, more than any other woman or man.
"I'd like to say congratulations to Simona, you had a great week, you played great, I hope you have many more finals and you will win it," said Ostapenko, who was a first-round loser at the tournament in 2016.
"I wish you good luck for the season."
Halep, the runner-up in 2014 also, hailed Ostapenko.
"I am upset but congratulations to Jelena, you are a great champion," said the Romanian, who would have taken the world number one spot with victory.
"Enjoy it. I am a little sick in the stomach but I want to win it one day. It's my dream."
She added: "It's a tough day today because I couldn't win but let's work, let's keep working, let's believe."
"Jelena, all the credit for what you have done. It's an amazing thing. Be happy & keep it going, because you're like a kid."
Halep had lost to Maria Sharapova in the 2014 final.
She saved a match point to beat Elina Svitolina in the quarter-finals and in the absence of Serena Williams, Sharapova and Victoria Azarenka, the 25-year-old was the overwhelming favourite.