Perth - World number one Caroline Wozniacki arrived in Australia just hours before her match but defied jet lag and fatigue to make a winning start at the mixed teams Hopman Cup on Monday.
She scored an impressive 7-6, 6-2 win over American Bethanie Mattek-Sands after flying in from Thailand, where she was playing in a charity event.
Wozniacki and unheralded team-mate Frederik Nielsen upset the pair of Mattek-Sands and Mardy Fish 7-5, 6-3 in the mixed doubles encounter, giving Denmark a 2-1 win over the United States in Group A.
Wozniacki said it was an unusual experience to play so soon after her arrival.
"It is the first time I have done that and I was bit nervous about how my body would feel," she said. "I didn't even make it back to the hotel, I went from the airport straight to the practice (court).
"But once I was out there I didn't even think about it."
In another Group A events on Monday, World number two Petra Kvitova and Tomas Berdych won singles matches to give Czech Republic a 2-1 victory over Bulgaria.
Wimbledon champion Kvitova opened her new campaign with a straight-sets win over Tsvetana Pironkova.
Although the 46th-ranked Pironkova was highly competitive, Kvitova had too much power, winning 6-4, 6-2 in 75 minutes.
Kvitova admitted there was added pressure on her heading into 2012 compared to 12 months earlier, when she was ranked 34th in the world.
"Every season is different," she said. "One year ago I was 34, now I am two at the start of the season and everyone is seeing me on the court for the first time, and it's not always easy to play on the court.
"The first match for the year is always tough, but I played well."
Kvitova, who is hot on the heels of rival Wozniacki, could secure the top world ranking within weeks.
After Kvitova's win, world number seven Berdych secured a hard-fought three-sets win over talented youngster Grigor Dimitrov in a high quality match, 6-4, 6-7 (9/11), 6-3.
Berdych had lost his only previous encounter to the gifted Dimitrov, but prevailed in what was a high-standard singles clash to start the year.
"He's going to be really dangerous this year," Berdych said. "It gives you even more confidence to have the first win of the year and even to play a really solid game like it was today, so I'm happy for that."