As the Australian Open gets under way, reigning champion Roger Federer stands in the way of Rafael Nadal's bid to win his fourth successive Grand Slam event.
"Roger and Rafa are the two guys that have played the best tennis in the Slams the last few years," said Britain's Andy Murray, the fifth seed. "They'd be the favourites but I think there are a lot of guys that can win against them if they play."
World number one Caroline Wozniacki is top seed in the women's tournament. But the majority of the pre-event publicity has focused on the men, with Federer, who is targeting a 17th Grand Slam, saying Nadal's success in the last three majors could see him become the first man since Rod Laver in 1969 to hold all four Grand Slams at the same time.
Organisers have decided to start the tournament by playing the bottom half of the draw on the Men's side and the top half of the draw on the Women's side.
Here are some of the highlights to follow on day one at the Australian Open :