World number four Andy Murray's build-up in his quest for a first grand-slam title had an uneasy start when he laboured to a 5-7 6-3 6-2 victory over the unheralded Mikhail Kukushkin in the Brisbane International first round on Tuesday.
Kim Clijsters's preparations for her Australian Open defence later this month were also given a severe shake-up when she squandered a blistering start before she beat Serbia's Ana Ivanovic 6-1 1-6 6-3.
Ivanovic had seemingly been on course for her first victory over the Belgian in five meetings when she rebounded to take a 3-1 lead in the final set before the fifth-seeded Clijsters fought back.
The four-times grand-slam winner broke the former French Open champion in the seventh game of the final set to take a 4-3 lead then held serve and broke the Serbian in the final game to advance to the quarter-finals after a roller-coaster 78 minutes.
Murray, who has recently recruited eight-times grand-slam winner Ivan Lendl as his coach in a bid to end his own grand-slam drought, also had a poor start when the Kazak went out to a 3-0 lead in the first set.
Kukushkin, ranked 91st in the world, then suffered stage fright on the main Pat Rafter Arena court and allowed the Scot back into the match though he was able to recover enough to seal the first set in just over an hour.
The first-set loss seemed to kick Murray, who had been limping earlier, into gear and he romped out to a 4-1 lead in the second and never looked back, with the final two sets taking less time than the first. He served out for victory in just under two hours 10 minutes.
The Scot has brought in Lendl to help him get over the last grand-slam hurdle after losing in three finals, including the last two at Melbourne Park.
The women's second and third seeds, Germany's Andrea Petkovic and Italy's Francesca Schiavone, advanced to the quarter-finals with Petkovic particularly impressive as she battled with a back injury.
The 10th-ranked German took a little while to get going after her tough three-set victory against Shahar Peer on Monday, and played into Czech Barbora Zahlavova Strycova's strengths before she ran out a 7-6 6-0 winner.
"Hopefully I'm going to have a day off tomorrow and then I can get rid of the pain because it's bothering me on the serve. I cannot really get good pop," Petkovic said.
"Right now from the baseline I feel very good. My movement is fine and my serve was fine also until this happened, so we will see what happens."
Former French Open champion Schiavone beat Kazakhstan's Galina Voskoboeva 6-4 6-4.