NEW YORK - For Victoria Azarenka, there were no regrets, just satisfaction that she had produced her best in her gallant US Open final loss to Serena Williams, a player she described as the greatest of all time.

At 5-3, 30-30 in the final set of her first final at Flushing Meadows, the world number one stood two points away from winning Sunday's title only to fall victim to yet another of Williams's great escapes as she went down 6-2 2-6 7-5.

Victoria Azarenka of Belarus reacts after her defeat to Serena Williams of the US in their women's singles finals match at the US Open tennis tournament in New York, Sept 9, 2012. [Photo/Agencies]

"I have no regrets," the Belarusian said. "I felt like I gave it all there. Could it have gone my way? Probably, yes. But it didn't.

"It really, really hurts. Those emotions come out and you feel sad, but it's time to really realize what happened today. It was a great match. It was close, but not for me."

Outplayed in the first set, Australian Open champion Azarenka raised her game in the second, extending the rallies and forcing uncharacteristic mistakes from Williams, who looked more tense by the point.

But as she has done so many times in her career, the 30-year-old pulled herself together when she needed to and reeled off four straight games to win her fourth US Open and her 15th Grand Slam singles title.

"For me she's the greatest player of all time," Azarenka said. "She took the game to the next level.

"She makes me always make sure that I'm taking my game, my personality, my physical aspect to the next level.

"Today I was close. I'm going to have, for sure, another opportunity to make something better. That's what I'm looking for."

Azarenka said she was proud of how she fought back into the match, having been blown off court by the power of Williams in the first set.

"I felt like I came up to do something different to provoke those opportunities," she said. "I wasn't (thinking that) she will start to miss because that will never happen."

"I felt like I provoked her and I was just trying to stay in that moment to make sure that I keep it rolling."

Azarenka said she was proud of her ability to produce her best form on the biggest stages.

"I feel like when the task is more difficult for me it's more exciting," she said. "(When) that fear, the adrenaline is coming, something that you never experienced before, you have to stand tall and just face it."

Having won a bronze medal at the Olympics and gone so close to a second Grand Slam title, Azarenka said she would take a short rest and reflect on her efforts.

"It's a great achievement (to get to the final), no doubt," she said. "I feel proud of myself in one way, but still sad. But in a few days when I go home, I'll be more than happy with the summer.

"I think I'm in pretty good shoes, sitting here as a finalist of the US Open actually for my first time."