Azarenka said journalists should focus on the quality of her match not the players' noise levels

Victoria Azarenka has defended her on-court grunting and insists former men's champion Rafael Nadal is louder than her.

The Belarusian was defeated in three sets by Serena Williams in Tuesday's Wimbledon quarter-final and faced post-match questions over her noise levels.

"I'm tired of these questions," she said. "It's annoying as guys grunt.

"I was practising next to Nadal and he grunts louder than me and nobody noticed it. Look at the good stuff."

Azarenka lost 3-6 6-2 6-3 in a high-quality match in front of 15,000 spectators on Centre Court and claimed the focus should have been on the standard of play rather than the noise levels.

She added: "Maybe it is time to put it aside and not talk about it all the time because this is not what is important when there are two players playing on Centre Court.

"Stop bringing up this ridiculous stuff. Let's put aside the noise, how she looks and look at the game. The game proved itself today."

Denmark's former world number one Caroline Wozniacki has recently raised the issue of sexism in the game, claiming women do not receive as many opportunities as men to play on Wimbledon's show courts.

"I would love to play on a big court," said Wozniacki. "The women really haven't gotten the opportunity here to play on the big courts. You only get one women's match on Court One and Centre Court.

"It's definitely different, that's all I can say. I think a lot of us women feel like we deserve to play on the big courts in front of a big crowd, as well."

Meanwhile, Williams' next opponent, Maria Sharapova, also deflected questions about her grunting during her victory over Coco Vandeweghe of the USA.

"I don't say anything. Do I have to?" said the Russian. "I have nothing to say. It's nothing new. It's not a new question."

Vandeweghe said afterwards that the noise from her opponent "didn't bother me whatsoever", but she did accuse her opponent of unsporting behaviour, claiming Sharapova had tried to put her off while she served.

"What I experienced, what I felt from her moving around in between my serving motion was not, I don't think, sportsmanlike," Vandeweghe said.

"She said she didn't believe she was doing it during the motion. I strongly disagreed."

Sharapova refused to be drawn on the accusations. "It is what it is," the 2004 Wimbledon champion said. "What she said, I'm not going to argue against her words."