France's Tatiana Golovin upset top seed and defending champion Nadia Petrova to win her first tour title at the Bausch & Lomb Championships in Florida.
Golovin took her head-to-head record against Petrova to 5-1
The 19-year-old beat Russia's Petrova 6-2 6-1 in one hour, 16 minutes.
"This is probably the happiest day of my life in my tennis career," said Golovin, ranked 20 in the world.
Golovin had been in excellent form all week on the green clay in Amelia Island, beating Venus Williams and Ana Ivanovic on her way to the final.
An aggressive Golovin opened the final with a service break and broke Petrova twice more on her way to the first set.
I feel like I've gone on to the next level in winning my first tournament
Petrova was well below her best and the second set disappeared even more quickly, with Golovin converting her second match point when her opponent fired a forehand long.
"I felt I was ready to win my first title today," said Golovin. "Today I knew I could beat Petrova. I knew I had the weapons to do it.
"I feel like I've gone on to the next level in winning my first tournament."
Petrova made 29 unforced errors in the 15 games and admitted it was uncharacteristic of her.
"Yes, very much (it is)," she said. "What I can say is that it is just a lack of concentration.
"In some situations I was going for too much in trying to finish it off. I didn't have enough energy really to stick in the balls today.
"I didn't have quite the desire either, especially after I lost the first set."