British number two Dan Evans impressed on his return from injury by beating Australian Rinky Hijikata in straight sets at the Adelaide International.
Competing for the first time since tearing his calf at the Vienna Open in October, he won 6-3 6-4 to set up a last-16 match against Alexander Bublik.
At the Australian Open, Britons Billy Harris and Ryan Peniston progressed to the second qualifying round.
But Lily Miyazaki was beaten on the first day of action in Melbourne.
Evans, 33, made a fast start under the Centre Court lights in Adelaide, forcing three break points in Hijikata's opening service game before breaking to 15 for a 3-1 lead.
The fleet-footed world number 40 produced several moments of brilliance and, although unable to make the most of five more break points two games later, he was untroubled in serving out a dominant first set.
Hijikata provided sterner resistance in the second but Evans took full advantage when the 22-year-old wildcard's level dropped in the ninth game - allowing him to serve out a satisfying victory.
"I was a little tired - it's my first match of the year - and it was important to keep focused," said Evans, who reached a career-high rank of 21 after winning the biggest title of his career at the Citi Open in Washington last August.
"It was a very good match to be part of and the crowd were very fair as well."
On his recovery from injury, he added: "It was challenging to get injured at the end of last year. It took a while to heal and I'm still looking after it. I'm still a little nervous but it feels all right."
Harris wins on Australian Open debut
Harris and Peniston both had to come through three-set matches to keep alive their hopes of qualifying for the Australian Open main draw for the first time.
The 28-year-old Harris, who has never made the main draw of the men's singles at a Grand Slam, recovered to beat Bulgarian Dimitar Kuzmanov 0-6 6-2 6-2 and set up a meeting with David Goffin.
Britain's eighth-highest ranked men's player and the world number 200, he earned his first match win on the ATP Tour at the Sofia Open in November to gain entry to the qualifying rounds in Melbourne.
Harris, who began his career driving between European tournaments is scheduled to face Belgium's former ATP top-10 player Goffin - the current world number 107 - in his second qualifying match on Wednesday.
Peniston will meet Tunisian Aziz Dougaz after finally taking his eighth match point against Sweden's Elias Ymer.
The 28-year-old missed four chances in the 10th game of the decider before producing a strong finish in the tie-break to clinch a 6-1 4-6 7-6 (10-7) win.
In the women's draw, Miyazaki lost to Australian 18-year-old Melisa Ercan, who was able to overcome calf cramps to edge a second-set tie-break and seal a 6-4 7-6 (7-5) win.
With the tournament playing catch-up after rain prevented any play on Monday, the other five British players in qualifying - Harriet Dart, Heather Watson, Francesca Jones, Jan Choinski and Oliver Crawford - had their opening matches pushed back to Wednesday.
They will each be hoping to join Harris and Peniston in the second of three qualifying rounds as they bid to reach the main draw of the year's first Grand Slam tournament, which starts on Sunday.
British number three Dart faces Italy's Nuria Brancaccio, Watson takes on Swiss player Lulu Sun, and Jones plays Margaux Rouvroy of France in the women's draw.
In the men's, Choinski opens against Lebanese-German player Benjamin Hassan, while Crawford, who recently switched from representing the United States, faces Belarusian Ilya Ivashka.
Vondrousova injury concern & Pliskova beaten
Wimbledon champion Marketa Vondrousova was forced to withdraw from the Adelaide International with a hip injury five days before the start of the Australian Open.
The Czech world number seven, who last year became the first unseeded player to win the Wimbledon women's singles title, pulled out before her opening match against Belarusian Aliaksandra Sasnovich.
Latvia's former French Open winner Jelena Ostapenko set up a last-16 match against Caroline Garcia by coming back from a set down to beat Romania's Sorana Cirstea 2-6 6-2 6-4.
World number 12 Ostapenko will face France's 20th-ranked Garcia, who also recovered from losing the first set to win 6-4 1-6 6-3 against 18-year-old Australian wildcard Taylah Preston.
But former world number one Karolina Pliskova - an Australian Open semi-finalist in 2019 - is out after falling to a 6-2 6-1 loss to Czech compatriot and qualifier Katerina Siniakova.
At the Hobart International, 2020 Australian Open champion Sofia Kenin safely progressed with a 6-3 6-3 win over Belgium's Greet Minnen.
However, former US Open winner Sloane Stephens lost her first-round match against China's Yue Yuan 6-4 3-6 7-6 (7-5).
