Serena Williams of the US poses with her trophy after winning the women's singles final match against Victoria Azarenka of Belarus at the US Open tennis tournament in New York's Central Park, Sept 9, 2013. [Photo/Agencies]

NEW YORK - Serena Williams admits that having love in her life has been a key to her rousing success over an exhilarating 13 months in which she has won Olympic gold, two US Open titles and a French Open.

Following a fitful night's sleep after winning her fifth US Open crown on Sunday in a three-set thriller over world number two Victoria Azarenka, Williams surprised a small group of reporters when asked about the power of love.

"Love? I think it's important to have it in your life, I guess. I'm not an expert on that subject," said Williams, whose stellar run coincides with her partnership with French coach Patrick Mouratoglou, who has also been linked romantically with the American world number one.

"Everyone says you get one. Some people say you get two. I'm definitely in love with tennis right now," Williams, a towering figure in crystal spike heels adorned in gold rhinestones and wearing a black blazer over a mini-dress, added coyly with a smile.

Williams, who will turn 32 later this month, became the oldest women's winner of the US Open since tennis turned professional in 1968 when she claimed her fifth US Open title.

The American world number one said she was having too much fun and success to contemplate leaving the tennis stage.

"I haven't thought of a number or age when I'm going to stop. I can tell you this: I don't see myself retiring any time soon and obviously there's some goals that I want to reach and things that I want to do."

Her latest US Open triumph increased Williams' haul of Grand Slam singles trophies to 17, one behind Chris Evert and Martina Navratilova, and five behind Steffi Graf. Australian Margaret Court rules the record books with 24.

As she moves up the all-time list, Williams has become aware of how she compares with the greatest players ever.

"I definitely want to continue to focus on Grand Slams and put the work into doing that," said Williams, who said she increased her tournament-load this past year, winning nine titles, in order to reclaim the world's top ranking.

"I just really am enjoying myself," she said. "This year I've played a lot more. I'm happy about that too, but I'm having a lot of fun."

Williams, who also played doubles with her older sister Venus at Flushing Meadows, may have shown her age in how she approached her celebration of the latest Grand Slam triumph.

"I had a little room service and I went to sleep. I was really tired," said Williams in a gravelly voice after just three hours of sleep.

"I had a long two weeks, with the doubles and the terrible scheduling at times. It wasn't very easy, so I was happy it was all over."