Cypriot Marcos Baghdatis made a winning return to Australia on Monday with a first-round victory at the Sydney International, while former women's world number one Martina Hingis crashed out.
Baghdatis crushed Latvia's Emests Gulbis 7-6, 6-1 in his first appearance Down Under since his fairytale run to last year's Australian Open final, while Hingis was knocked out by Jelena Jankovic.
The in-form Jankovic followed up her victory in Saturday's Auckland Classic final with a 6-4, 4-6, 6-3 win over Hingis, who suffered her second defeat in three days having lost the final of the Australian women's hardcourt championship to Dinara Safina.
Serbian Jankovic should have wrapped up the match in straight sets after winning the first and racing to a 4-2 lead in the second before she began to tire.
She started to feel pain in her lower back and called for a trainer to take her blood pressure after Hingis rolled off four games in a row to force the match into a deciding set.
"I just came from Auckland so I didn't have much time to recover, I was quite proud of how I managed to pull through," she said.
"I've had better wins than this but obviously it's a great win for me and gives me a lot of confidence."
Jankovic, who reached the US Open semi-finals last year in her best performance yet at a grand slam event, will play Australia's Samantha Stosur in the second round after she beat Russian Vera Zvonareva 6-1, 6-4.
Jankovic is ranked 12th in the world, five places below Hingis, but missed out on a seeding for Sydney because of the depth of the event, with Maria Sharapova the only player in the top 10 who did not enter the tournament.
World number one Justine Henin-Hardenne withdrew last week for personal reasons.
"Pretty much everyone is here, it's an amazing draw," Hingis said. "Well, at least I'll get a few days off."
Baghdatis also had to call for the trainer to massage his hip after the first set of his centre court clash at Sydney's Olympic tennis centre.
Still jet-lagged after flying into Sydney from Doha, the 21-year-old said he was battling the twin problems of soreness and fatigue but expected to recover with some rest.
"After we massaged it, it was getting better," he said. "I still have a bit of pain but by treating it, it will go away."
Baghdatis will play Jan Hernych on Wednesday for a place in the quarter-finals after the Czech qualifier upset last year's runner-up, Italian Andreas Seppi, 6-4, 6-2.
Fifth-seeded Czech Tomas Berdych also advanced, beating Australian qualifier Robert Smeets 6-2, 7-5, but eighth-seeded Frenchman Sebastien Grosjean suffered a 6-4, 6-4 defeat at the hands of Spain's Fernando Verdasco.