With temperatures heating up in Melbourne, the two Grand Slam winners wasted little time on court. Sharapova, still working her way back from a 15-month ban for taking the performance-enhancing substance meldonium, showed glimpses of the tennis that made her a five-time major winner.
The 2008 Melbourne Park champion, now ranked 48, battled past Germany's Tatjana Maria 6-1, 6-4 and will next play either 14th seed Anastasija Sevastova of Latvia or American Varvara Lepchenko.
"I cherish these moments. I love it here," said the Russian, who returned from her drugs ban in April last year. "It's been a couple of years and I wanted it to be really meaningful to me." Fellow former world number one Kerber, who won the tournament in 2016, was also impressive in dismissing Anna- Lena Friedsam 6-0, 6-4.
"2017, I have said goodbye already, I am not looking back," she said after a forgettable last season that saw her relinquish the number one spot and slide down the rankings. She is now on a 10-match win streak after a perfect early season. "I'm just trying to enjoy it again on court," said the German, who turns 30 this week.
Sixth seed Karolina Pliskova and eighth seed Caroline Garcia also progressed, in contrast to the other side of the draw that saw Venus Williams, Sloane Stephens and Coco Vandeweghe crash out yesterday. American woes continued with Madison Brengle sent packing by British ninth seed Johanna Konta.
Auckland Classic champion Fernando Verdasco was among men to make the second round, with a straight-sets win over 20th seed Roberto Bautista Agut. But Raonic, who has made at least the last eight over the past three years in Melbourne, was bundled out by 86th-ranked Slovakian Lukas Lacko in four sets. It was his earliest Grand Slam exit in seven years as he fights back from a wrist injury.
Roger Federer, rated as favourite to win his 20th Grand Slam title even at the venerable age of 36, makes his entrance in a night match on Rod Laver Arena. The second seeded Swiss, who is coming off an extraordinary 2017, when he won a fifth Australian Open title and a record eighth at Wimbledon, faces Slovenia's Aljaz Bedene.
Twelve-time Grand Slam winner Novak Djokovic is also in action, amid reports he is leading a push to create an independent players union to fight for even more prize money. The Serb, returning from a long break with an elbow injury, plays American Donald Young on Margaret Court Arena. Fellow injury-plagued star Stan Wawrinka also makes his comeback from injury today.
World number one Simona Halep takes the court later as she chases a first Grand Slam title, with Wimbledon champion and third seeded Garbine Muguruza making her bow in an evening match. Former world number one Pliskova was among those to move smoothly into the second round, with a steady 6-3, 6-4 win over Veronica Cepede Royg. The tall tattooed Czech, who made the quarter-final in Australia last year, was largely untroubled and is looking for a deep run at the tournament.
"I'll take it match by match and I think I have a good chance," she said. Sydney-born Konta also made the last eight in 2017 and showed no signs of her recent hip injury as she dismantled Brengle 6-3, 6-1. She can't wait for her next match on Thursday even though temperatures are forecast to hit 40 Celsius (104 Fahrenheit) later in the week. "I look forward to the heat, I love it," she said. (PTI)