Defending champion Victoria Azarenka and five-time winner Serena Williams both recorded easy second-round victories, while Roger Federer also cruised through on a humid day four at the Australian Open.
Britain's Andy Murray also won comfortably while Laura Robson overcame world number eight Petra Kvitova in a three-hour battle to join Heather Watson in the third round at Melbourne Park.
Rod Laver Arena
Victoria Azarenka (Blr)  beat Eleni Daniilidou (Gre) 6-1 6-0
The defending champion powered to victory in 55 minutes to reach the third round. The world number one will next play American Jamie Hampton in the next round.
"I definitely stepped it up from my first match, and I was in the zone trying to execute all of my shots," said the Belarusian. "I was trying to make everything happen, and that's what I'm happy about."
"It was pretty hot. That's why I was trying to play fast. The first match I got a little bit sunburned and you don't want to make that mistake again."
Serena Williams (US)  beat Garbine Muguruza (Spa) 6-2 6-0
The third seed brushed aside any injury worries as she raced into the third round. The American hurt her ankle in the first round but was moving freely in her victory over the Spaniard.
The only mishap came when Williams hit herself in the mouth with her racquet. "One day I twist my ankle, today I hit myself in the face - I don't know what's going to happen on Saturday," she said.
"I'm hoping maybe I'll just hit some winners. I thought if there's swelling, at least I'll get super-sexy lips, right?"
Williams next plays Japan's Ayumi Morita as she continues her bid for a 16th Grand Slam title and a sixth at Melbourne Park.
Bernard Tomic (Aus) beat Daniel Brands (Ger) 6-7 (4-7) 7-5 7-6 (7-3) 7-6 (10-8)
Tomic delighted the home fans by beating the German qualifier to set up a potential third-round match with Roger Federer. The 20-year-old exchanged a few words in the media with Federer in the build-up to the tournament, but is unbeaten this year having won his first ATP title in Sydney earlier this month.
Roger Federer (Swi)  beat Nikolay Davydenko (Rus) 6-3 6-4 6-4
Davydenko was brushed aside by Federer in just 119 minutes, with the Swiss master now set to face the last Australian left in the competition, Bernard Tomic.
Laura Robson (GB) beat Petra Kvitova (Cze)  2-6 6-3 11-9
Robson, 19 on Monday, recovered from 3-0 down in the final set to come though a three-hour thriller.
Maria Kirilenko (Rus)  beat Shuai Peng (Chn) 7-5 6-2
Andy Murray (GB)  beat Joao Sousa (Por) 6-2 6-2 6-4
Murray won in one hour and 41 minutes and will face qualifier Ricardas Berankis of Lithuania in the third round.
Caroline Wozniacki (Den)  beat Donna Vekic (Cro) 6-1 6-4
Former world number one Wozniacki produced a good display to see off her resilient 16-year-old opponent. Vekic is based in London and is coached by Tim Henman's former coach David Felgate.
"I'm starting to feel seriously old because all the players at a physio session recently were younger than me," said Wozniacki. "I was even asked about retiring but I'm only 22!"
Gael Monfils (Fra) beat Lu Yen-Hsun (TPE) 7-6 (7-5) 4-6 0-6 6-1 8-6
Margaret Court Arena
Jo-Wilfried Tsonga (Fra)  beat Go Soeda (Jpn) 6-3 7-6 (7-1) 6-3
Svetlana Kuznetsova (Rus) beat Su-Wei Hsieh (TPE)  6-2 6-1
Julia Goerges (Ger) / Samantha Stosur (Aus) beat Daniela Hantuchova (Slv)  / Anabel Medina Garrigues (Spa)  6-3 6-1
Marcos Baghdatis (Cyp) / Grigor Dimitrov (Bul) v Matthew Ebden (Aus) / Ryan Harrison (US) 7-6 (8-6) 6-2
Juan Martin Del Potro (Arg)  beat Benjamin Becker (Ger) 6-2 6-4 6-2
Andy Murray (GB)  beat Joao Sousa (Por) 6-2 6-2 6-4
Laura Robson (GB) v Petra Kvitova (Cze) 
Jonathan Marray (GB)  / Andre Sa (Brz)  beat Lukas Lacko (Svk) / Igor Zelenay (Svk) 4-6 7-5 7-6 (7/5)
Marina Erakovic (NZ) / Heather Watson (GB) lost to Anna-Lena Groenefeld (Ger)  / Kveta Peschke (Cze)  6-4 6-0
Jamie Delgado (GB) / Ken Skupski (GB) lost Tomasz Bednarek (Pol) / Jerzy Janowicz (Pol) 6-0 6-7 (2-7) 6-3
Treat Conrad Huey (Phi) / Dominic Inglot (GB) lost to Max Mirnyi (Blr)  / Horia Tecau (Rom)  6-7 (4-7) 7-6 (10-8) 6-3
Heather Watson (GB) v Agnieszka Radwanska (Pol)  at 00:00 GMT on Friday
Ricardas Berankis (Lit) beat Florian Mayer (Ger)  6-2 6-3 6-1
Qualifier Berankis hammered 25th seed Mayer in straight sets to set up a third-round match with Andy Murray, with whom he practised in Brisbane earlier this month.
"I'm feeling confident at the moment, that's for sure," he said. "I feel quite calm, it's not going to be a big surprise to see Andy Murray on the other side of the net."
Bojana Jovanovski (Serbia) beat 17-Lucie Safarova (Czech Republic) 7-5 7-5
Elena Vesnina (Rus) beat Varvara Lepchenko (US)  6-4 6-2
Kimiko Date-Krumm (Jpn) beat Shahar Peer (Isr) 6-2 7-5
The 42-year-old Date Krumm, who became the oldest woman to win a main draw match at the Australian Open when she beat 12th seed Nadia Petrova on Tuesday, set another record with her latest victory.
The Japanese veteran became the oldest player to make a Grand Slam third round since 45-year-old Renee Richards in 1979.
Date-Krumm, who has attributed her longevity to leading a simple life, said she gets a lot of support from fellow players. "Everybody says to me, 'You are crazy'. First word is always, 'You are crazy'. But they support me a lot," she said.
Stats of the day
Faltering Frenchman: Serving for the match at 7-6 in the fifth set against Lu Yen-Hsun of Taiwan, Gael Monfils missed his first match point in regulation fashion and then hit four double-faults in a row, part of a total of 29 from the Frenchman in the match. Monfils finally converted his sixth match point with a service winner.
Ace count - Gael Monfils - 55; Petra Kvitova - 21
Total winners - James Duckworth - 137; Ana Ivanovic - 73
Most challenges won - James Duckworth - 6; Valeria Savinykh - 4
Fastest serve - Jerzy Janowicz (141.7mph, 228kph); Serena Williams (128.7mph, 207kph)
Quote of the day
Laura Robson after her epic win over Petra Kvitova: "I am actually amazed so many people stayed to watch. I thought they would all leave after Federer ['s match against Nicolay Davydenko]."