US Open champion Serena Williams has revealed that she was able to block out Victoria Azarenka's grunting during last night's final at the US Open.

World number one Azarenka has built up the reputation as one of the loudest grunters in the women's game while playing a shot.

Despite admitting that she has been put off by the shrieks during past matches between the two, Williams insisted that she was too focused during their latest title encounter.

"It was so funny usually I do hear her grunting," the 30-year-old told CBS This Morning. "We've played so many times this year at Wimbledon as well but I promise you, in this particular match, I didn't hear anything because during the match I remember thinking, 'Wow, she's pretty low today.'

"I literally thought about that. But for me, I get so used to it. I'm such in the zone and she's not doing it to distract anybody, it's just how she grunts."

Williams has now emerged victorious from the tournament at Flushing Meadows on four occasions.