Second seed Ons Jabeur overcame a second-set wobble to beat Tamara Zidansek and reach the second round of the Australian Open.
Jabeur, 28, is bidding for her first Grand Slam title after being runner-up at Wimbledon and the US Open last year.
There were also wins for Caroline Garcia, Aryna Sabalenka and Karolina Pliskova on the second day of play.
Jabeur has never gone beyond the quarter-finals in Melbourne but is among the favourites for the title after her strong Grand Slam showing last year.
"It was a very tough match. I wasn't playing very well and she was putting pressure on me," Jabeur said.
"I was pretty frustrated. I just told myself to be number two in the world and win this match."
French fourth seed Garcia cruised into the second round with a 6-3 6-0 win over Canadian qualifier Katherine Sebov. She will face another Canadian in 2021 US Open runner-up Leylah Fernandez after her 7-5 6-2 win over Alize Cornet.
Fifth seed Sabalenka of Belarus registered a 6-1 6-4 victory over Tereza Martincova to set up a tie with American Shelby Rogers, while former world number one Pliskova beat China's Wang Xiyu 6-1 6-3.
Belgian Elise Mertens fought back from a set down to beat 2020 finalist Garbine Muguruza 3-6 7-6 (7-3) 6-1 and 12th seed Belinda Bencic completed a 6-1 6-2 win over Viktoriya Tomova of Bulgaria.