The win, her first on clay court, broke a nearly two-year drought for the eighth seeded American, who claimed her fourth career title.

Her previous two losses to Denmark’s Wozniacki had been on hard courts when Keys failed to win a set.

“I think I served really well today, said Keys, who had predicted on Saturday that playing on clay would be beneficial in her bid to defeat Wozniacki.

“I also felt I kept a lot of pressure on her, making a lot of returns and keeping rallies going and not going for things too early,” said the world number 18, who won 76% of points on her first serve, and fired six aces. “More than anything I really trusted my game and went for my shots.”

That was most evident late in the first set and the tiebreak.

The big-serving Keys trailed 5-6 in the opening set before forcing the tiebreak, which remained close until 4-3 when the fifth-seeded Wozniacki double faulted.

Keys won the next point but twice had backhand errors to allow Wozniacki to pull within 6-5.

A backhand down the line enabled Keys to finally claim the set.

“I just knew the games I was losing in the first set I was just being too tentative and not really trusting my shot,” said the 24-year-old American.

“I knew I had to go for it. I think that’s how I have to play… 100% believing in my game.”

Keys broke Wozniacki in the sixth game of the second set to go up 4-2 and when she made it 5-2 that all but clinched the match.

“It’s definitely been a really great week for me, especially after having some really tough losses the last couple of weeks,” Keys said. “It definitely is a very good springboard for heading over to Europe.”