Serena Williams hit the ground running at Melbourne Park for the first time since her 2017 title win, taking just 49 minutes to wrap up an opening round win but the day session was tough for a host of others.
ROD LAVER ARENA
(17) Madison Keys (USA) vs Destanee Aiava (AUS) 6-2 6-2
(16) Serena Williams (USA) defeated Tatjana Maria (GER) 6-0 6-2
(4) Alexander Zverev (GER) defeated Aljaz Bedene (SLO) 6-4 6-1 6-4
(1) Novak Djokovic (SRB) vs Mitchell Krueger (USA)
(4) Naomi Osaka (JPN) vs Magda Linette (POL)
MARGARET COURT ARENA
Kamil Majchrzak (POL) retired hurt vs (8) Kei Nishikori (JPN) 6-3 7-6 0-6 2-6 0-3
Tamara Zidanesk (SLO) defeated Daria Gavrilova (AUS) 7-5 6-3
Venus Williams (USA) defeated (25) Mihaela Buzarnescu (ROU) 6-7 7-6 6-2
(1) Simona Halep (ROU) vs Kaia Kanepi (EST)
Benoit Paire (FRA) vs (7) Dominic Thiem (AUT)
(7) Karolina Pliskova (CZE) defeated Karolina Muchova (CZE) 6-3 6-2
(11) Borna Coric (CRO) defeated Steve Darcis (BEL) 6-1 6-4 6-4
Laura Siegemund (GER) defeated Victoria Azarenka (BLR) 6-7 6-4 6-2
Dayana Yastremska (UKR) defeated Samantha Stosur (AUS) 7-5 6-2
Nick Kyrgios (AUS) vs (16) Milos Raonic (CAN)
Casualty count rises
Ernests Gulbis became the latest casualty in Melbourne when he retired after taking the first set off Stan Wawrinka.
The Swiss was gifted a pass into the second round when the World No. 83 became troubled by a lower back issue that forced him to pull the plug.
It was the fifth retirement on day two of the Open — all on the men's side.
Earlier, Australian Thanasi Kokkinakis and Polish qualifier Kamil Majchrzak both failed to complete their matches because of injury and cramp respectively.
In other matches, Venus Williams bounced back to win a three-setter against Mihaela Buzarnescu, Canadian young gun Denis Shapovalov beat Pablo Andujar and Jo-Wilfried Tsonga overcame Martin Klizan 6-4 6-4 7-6 (7-5).
Stosur's shocking collapse
Sam Stosur lost five straight games to give up the first set to World No. 59 Dayana Yastremska before going on to lose the match.
Stosur was up 5-2 but somehow lost the opening set 7-5 to the 18-year-old, who was playing just her second grand slam match.
The Aussie has a horror record at her home grand slam, having lost in the first round of the 2018, 2017 and 2016 editions of the tournament.
"I'm not sure that even she knows what happened next," a Channel 9 commentator said in reference to Stosur's promising start falling to pieces.
The second set took a worrying turn when the hometown hero was broken, going down 3-1 before the teenager broke Stosur again to take a 4-1 lead.
"She can't quite believe this, what's happening," the same commentator said as Stosur stared down the barrel of another first-round defeat.
Playing in her first ever Australian Open, Yastremska kept her foot on the throat and won the match 7-5 6-2 to send Stosur packing early once again.
Crushed Kokkinakis retires
After going through qualifying to enter his home grand slam the hard way, Thanasi Kokkinakis said it was one of the sweetest achievements of his career.
But it all turned to heartbreak when the Aussie young gun was forced to retire during the second set of his opening round match against Taro Daniel from Japan.
Kokkinakis won the first set 7-5 but was hampered by a pec injury that required medical attention.
"I can't hit a serve over 140(km/h) ... it's embarrassing," Kokkinakis told the physio.
The pain became too much to handle when trailing 4-2 in the second set and the star left the court looking absolutely shattered.
"That is shattering for the Australian," a Channel 9 commentator said. "Too many times we have seen him injured throughout the course of his career. We have seen it here on the big stage. He will be shattered right now."
Another commentator added: "I can understand why he was so frustrated ... It is a shattering blow that he is continually dealing with body issues as he is trying to make his way up the ATP ranks."
Serena's cold response
Serena Williams only refused to answer one question following her first round thrashing of Germany's Tatjana Maria — the one question the whole tennis world wants to know.
The 37-year-old American champion spoke warmly in her post match press conference, except for the moment she was asked to speak about her US Open final meltdown when losing to Naomi Osaka.
Williams' controversial tantrum and the chair umpire penalty that preceded it remain some of the biggest talking points in tennis right now, but it's the one subject Williams refuses to respond to.
"I like literally have no comment," Williams said when asked if she has spoken to coach Patrick Mouratoglou about their on-court systems since she was penalised for being coached by Mouratoglou from the stands at Flushing Meadows last year.
Williams has been criticised for having a low profile start to the year, choosing not to stage media interview opportunities in the lead-up to the year's first grand slam.
Tennis commentators have suggested Williams' behaviour reinforces her refusal to backtrack from the accusations she made towards tennis officials and umpire Carlos Ramos at the US Open.
However, Williams said on Tuesday her decision to stay out of the spotlight in 2019 is simply the result of her new life as a mother of daughter Alexis Olympia.
"I've been spending a lot of time with my daughter. I feel like that's the priority for me," she said.
"As a working mum, I feel guilty. I want to spend every chance I get with her. These are years I'll never get back."
Bouchard sizzles in round one
Eugenie Bouchard wasted little time in kicking off her Australian Open campaign in style, breezing through her clash with wildcard Shuai Peng 6-2 6-1.
The Canadian took 28 minutes to claim the opener before racing through the second set to finish the match in under an hour.
After her ranking fell off a cliff last year, Bouchard had a brighter start to 2019 when she made the quarter-finals of the ASB Classic in Auckland — a performance which came after she progressed to the semi-finals of an event in Luxembourg to close out 2018.
Bouchard will face Serena Williams in the second round.
'It's too much': Star's retirement heartbreak
An Australian Open star wept on court after his dream result turned into ash in a difficult to watch incident that dragged out his torment for a full hour.
Polish qualifier Kamil Majchrzak had performed one of the toughest to watch retirements witnessed at the Australian Open when he fought on for more than an hour, despite being unable to move.
Majchrzak was on the verge of the biggest win of his career after charging through the first two sets against No. 8 seed Kei Nisjikori — but a series of cramping attacks saw him collapse to the court on several occasions in the final three sets.
The 23-year-old's body failed him in the final three sets, where he went stiff as a board due to the cramping and was unable to even jog around the court.
Despite his constant pain, Majchrzak refused to throw in the towel. It created a harrowing scene where Nishikori had to play out the final three sets, despite the Polish talent being unable to chase down any of the shots that came back to him over the net.
He appeared in agony and on several occasions collapsed.
He called for a trainer in the third set and opted against taking a bathroom break because he would have to walk all the way to a bathroom off the court.
Nishikori breezed through Majchrzak like he was nothing from that point on, winning 12 of the 14 service games in the third and fourth sets.
Nishikori eventually triumphed when Majchrzak officially retired down 3-6 7-6 6-0 6-2 3-0.
Majchrzak threw in the towel when his request for a trainer was knocked back because cramp does not constitute a medical emergency.
He was left devastated by the retirement and held his hands in his towel to briefly try to hide the tears in his eye.
"In the end he just said, 'This is too much, can I please stop,'" commentator Geoff Masters said on Channel 9 of Majchrzak.
The heartbreaking scenes of Majchrzak grimacing across the court for more than an hour after the cramps started in the third set captured the attention of the world's gaze at Melbourne Park.
Some of the international tennis commentators assembled in Melbourne labelled Majchrzak's effort as brave, while others lamented the torture he put his body through by refusing to retire when the cramps first began.
Some on social media suggested it was the young qualifier's fault for not being in good enough physical condition, but Andy Murray's mum Judy came out with a reality check on Twitter.
"I have to say my opponent had it today," Nishikori said. "He played much better than I thought he would."
Outrage over water bottles at Aussie Open
For the second year running, the Australian Open's choice of bottled water has left Aussies scratching their heads.
Fans turned out in droves to be a part of day one of the Melbourne-based grand slam yesterday. But not everybody was satisfied.
In the stands, fans were questioning why Open organisers chose to import bottled water from China.
"In what universe do we need to import bottled water?" journalist and tennis fan Rachel Baxendale wrote on Twitter.
Her comment, which featured pictures of the water labelled "Australian Open official water", was retweeted more than 500 times and received more than 250 comments.
Among those chiming in was Senator Derryn Hinch, who suggested the money was too good for organisers to refuse.
"In a universe where the deal was worth millions of dollars a year to Tennis Australia," he wrote.
The move to Ganten, a company based in Shenzhen since 1992, was downplayed by organisers last year.
In a statement, Tennis Australia said the Australian Open was a global event with "a long history of partnering with international brands".
"Ganten water is a premium brand that is associated with other major tennis and sporting events.
"The Australian Open continues to expand its global reach and partnerships, which helps to grow the sport at all levels in Australia."
Tennis Australia did not respond to a request for comment this year.
Some commenters on social media were quick to point out that Aussies appeared to have no problem when French-based water company Evian sponsored the Open.
"The current outrage about Chinese bottled water being sold at the Australian Open is quite an amount larger than the days when Evian was the 'official water'," Preston Towers wrote on Twitter. "No prize for guessing as to why that would be."
Others suggested the Open should ditch single-use plastic bottles altogether.
"Idea for next year: Ditch the one-use plastic, provide water fountains and if people don't bring their own drink bottle make them buy one," Alexandra McKiernan wrote.
"No need to buy bottled water. BYO container and use fountains," Sarah Banks wrote.
The Australian Open counts the following international sponsors as official partners: Emirates, DeRucci, Haagen-Dazs, Lavazza, Toshiba and Piper-Heidsieck.
Lineswoman goes off
An unnamed lineswoman left the court after copping a blow from to the back during Fabio Fognini and Jaume Munar's clash at 1573 Arena.
The pair's Round of 128 match-up was briefly stalled as the official was escorted from the venue with her hand over her face in apparent pain. The playing pair were forced to wait until a replacement umpire arrived.
The official was seen on court a few minutes later and received a clap from the Melbourne crowd.
Kid jumps in the spotlight
Sometimes the stage is lit and nobody is there to fill it. Enter: this kid.
Luckily, the normally mundane coin toss was made all the more exciting after an Open ball boy well and truly went beyond the call of duty, completing a little kick and spin before flipping the 50c for Kei Nishikori and Kamil Majchrzak.
Rumour has it he's in a Michael Jackson cover band.
Carpe diem, little dude, carpe diem.
Tomic opens up the heart of Australian tennis
While the eyes of the tennis world were on Andy Murray, Bernard Tomic produced an honourable loss to Australian Open sixth seed Marin Cilic.
Then he blew it all up by launching a scathing attack on Australian Davis Cup captain Lleyton Hewitt as he suggested bias and promotion of players loyal to Hewitt and his management company — and in doing so implicated both Nick Kyrgios and Thanasi Kokkinakis ahead of their Australian Open starts.
"We have a lot of issues that not a lot of players are happy about," Tomic said when first asked if he expects to play Davis Cup this year.
"The players that I have spoken to aren't. Myself, Kokkinakis, Kyrgios. I think once that sort of gets resolved we'll see. I stand by my call a couple years ago. I knew something was wrong in the Davis Cup. And now there is Kokkinakis and Nick as well who aren't playing because they have issues with some people. Hopefully that can be arranged and the best players can be playing for Australia."
The tirade sent social media into meltdown but some analysts seem to think Tomic may have hit a nerve, even if his point was made at the wrong time.
Unsurprisingly other tennis luminaries came out to support Hewitt. Todd Woodbridge led the charge and described it as a "poor attempt to deflect".
"One of the most disappointing things here is it's become his habit of deflecting a loss and deflecting what work he does to try to get better as a tennis player," Woodbridge told 3AW Radio.
"Lleyton copped it last night. The last one that copped it, at Wimbledon a couple of years ago, was Pat Rafter.
"Now, I've been in spaces in development that have been around Bernie and I can promise you that myself, Pat Rafter, Lleyton Hewitt — who have all got a wealth of experience in this game, both as players and dealing with media and trying to help our next generation — have given him enormous amounts of our personal time.
"I've been away from my family and kids, as Pat Rafter did, as Lleyton Hewitt has, to enhance Bernard's career. So it's time he actually used some of the things that we've given him, the tools, and try to just get his tennis back on track.
"Last night was a poor attempt to deflect that he hasn't been doing that."
Hewitt's manager, David Drysdale, said the former world number one would speak on Tuesday afternoon.
"I'm not going to comment on it … there is a number of inaccuracies and I'm sure Lleyton will address all of that this afternoon," Drysdale told SEN Mornings.
Longtime Hewitt doubles partner Sam Groth expects a strong return serve.
"I'm not sure he's going to hold a lot back to be honest," Groth told SEN.
"I think he's bitten his tongue for a long time on this stuff and I think it's time to address it and put it to bed.
"In a time where we should be celebrating Australian tennis in the country, we're talking about a guy who has bowed out in straight sets in the first round and we haven't really spoken about because this time last year he was off doing reality TV.
"All of a sudden we're talking about him again when we have so much more to talk about."
Djokovic and Williams set to take the court
Novak Djokovic and Serena Williams, with 13 Australian Open titles between them, play their first-round matches Tuesday at what is expected to be a steamy Melbourne Park.
Williams, who has seven Australian titles and last won here in 2017, plays Tatjana Maria in the second match at Rod Laver Arena.
Top-seeded Djokovic, who will attempt to win a men's record seventh Australian title, opens night play on the same court against American Mitchell Krueger.
The temperature was already 30 degrees Celsius (86 Fahrenheit) when play began on all courts shortly after 11 a.m. local time and it was expected to rise by several degrees.
The sun and humidity added to the sultry conditions, forcing many of the early spectators to take relief by standing under giant cooling mist machines.