Danish tennis star Caroline Wozniacki has described Serena Williams's body as "amazing" after the world number one faced criticism over her figure.

The 33-year-old American, who is on course to claim a calendar Grand Slam at the US Open, was recently labelled 'manly' by Twitter trolls.

During an interview with United Airlines' in-flight magazine Rhapsody, Wozniacki said: "Serena has an amazing body - she has the curves and she's rocking it.

"A lot of people would be jealous of her body because it's amazing. Athletes in general have good bodies. We are toned, we're strong, and it's all about embracing that."

Wozniacki will begin her US Open campaign at Flushing Meadows with a first-round match against Jamie Loeb today.