Former number one Jelena Jankovic became the first women's seed to fall at the Medibank International on Monday as the Serb was ambushed by Hungary's Agnes Szavay 5-7, 6-1, 7-5.
Jankovic, who finished atop the WTA table in 2008, admitted she was taken by surprise despite two months of training and preparation for the new season. She now has a week to prepare for the Australian Open, where she played a semi-final two years ago.
"It was my first match of the season, and I was a little bit nervous, especially not playing for two months," the seed said.
"I just want to stay positive, and I hope that I will be ready for Melbourne," she said.
There was no luck either for eighth seed Vera Zvonareva with the injured Russian lasting only six games before quitting to hand compatriot Elena Vesnina a 3-3 trip to the second round on a steaming summer day.
Maria Jose Martinez Sanchez, who helped Spain to the Hopman Cup title at the weekend, maintained championship form over American Varvara Lepchenko 6-3, 6-3 while Flavia Pennetta, losing finalist in Auckland, recovered from that defeat against Australian Samantha Stosur 6-4, 6-1.
In the men's draw at Olympic Park, Frenchman Richard Gasquet, losing quarter-finalist in Brisbane last week, reached the second round over Spain's Feliciano Lopez 6-1, 6-4.
Pablo Cuevas of Uruguay defeated Michael Llodra of France 6-2, 7-6 (7-1) but there was even worse news for a third Frenchman, top seed Gael Monfils. A lingering shoulder injury led him to withdraw on Monday.
Monfils had dropped hints last week in Brisbane that he would be in a race against time if he was to be ready for Sydney. With the Australian Open starting in a week, the number 13 now faces a fresh deadline.
"It was getting worse and worse," Monfils said of his shoulder. "I had a little hope to be a bit better, but ... if I keep playing on it, it's gonna turn into something chronic."
Marcos Baghdatis, a 2006 Australian Open finalist, stepped onto court two months after his last appearance, a title at Stockholm, and made a winning impression on young Australian Nick Lindahl 6-2, 7-5.
After several tough seasons, the Cypriot was pleased to be pain-free and able to concentrate on his game.
"It's been now six months that I'm out of injuries, so, touch wood, I want to keep it that way," he said. "It's nice to be back and work every day without feeling any pains."
Another Aussie unknown went down on the day as Italian Andreas Seppi beat Marinko Matosevic 6-4, 6-4 with the winner next set to line up against four-time champion Lleyton Hewitt in the second round.