Five-time champion Serena Williams was made to work before joining fellow big guns Petra Kvitova, Vera Zvonareva and Maria Sharapova in the second round of the Australian Open on Tuesday night.
But No.6 seed and local hope Sam Stosur crashed out in straight sets to Romanian Sorana Cirstea, who prevailed 7-6 (7-2) 6-3 in the biggest upset on day two of action.
A visibly frustrated Williams overcome some stubborn resistance from world No.45 Tamira Paszek in her 6-3 6-2 win, which didn't finish until close to 1am local time.
The 12th seed looked like a woman on a mission in the early stages as she powered through her opening service games, but Paszek more than held her own until the eighth game when Williams finally got the break she needed to take the opening set.
The plucky Austrian wasn't about to go away though and held her opening two service games of the second set, before Williams suddenly came to life and asserted her physical dominance in taking the final five games of the match inlcuding a perfect service game that featured four consecutive aces.
Her power hitting resulted in 34 winners, but a rather high 26 unforced errors will be of slight concern ahead of her next match against Czech Barbora Zahlavova Strycova, who defeated Frenchwoman Iryna Bremond 6-0 6-4.
Sharapova, the 2008 champion at Melbourne Park who is seeded fourth this year, needed just 58 minutes to cast aside Argentine Gisela Dulko 6-0 6-1, with Dulko's only game coming when the Russian lost her way in the third game of the second set.
She may have battled in the heat in previous visits to Melbourne but Sharapova proved too strong on Tuesday, apart from some wayward serving in the second set both when she was broken after leading 40-0 in the third game and when she rallied from 0-40 when serving for the match.
Apart from hitting 14 winners to just four, the other major difference for Sharapova was converting six of nine break points to Dulko's one from five, booking Sharapova a second-round meeting with American Jamie Hampton who crushed Mandy Minella of Luxembourg 6-1 6-1.
Twelve months after reaching the quarter-finals in Melbourne, Wimbledon champion Kvitova breezed past Sharapova's fellow Russian Vera Dushevina in only 61 minutes, the Czech second seed breaking three times in each set en route to the 6-2 6-0 victory.
Kvitova dropped her serve just once in her match - in the second game courtesy of a double fault - but from there she reeled off the final 12 games to set up a round-of-64 battle with Spaniard Carla Suarrez Navarro after she beat Romanian Irina-Camelia Begu 6-1 7-5.
The most telling measure of Kvitova's dominance was the fact that she struck 19 winners to just seven from Dushevina, who won just 37 percent of points on her own serve in the one-sided encounter.
Two-time Melbourne Park semi-finalist Zvonareva had a much tougher time of it against Romanian Alexandra Dulgheru, dropping the second set along the way to a hard-fought 7-6 (7-4) 6-7 (5-7) 6-3 victory that earns her a clash with Czech Lucie Hradecka, who beat Russian Evgeniya Rodina 6-3 6-1.
Fresh off her upset win over Stosur, Cirstea will now fancy her chances of advancing to at least the third round, with Urszula Radwanska waiting for her in the round of 64