Photos from Day 1 of the Australian Open matches, played at Melbourne Park
A rampaging Roger Federer kicked off his 17th Australian Open campaign with a 6-2, 6-1, 6-2 demolition of Georgian battler Nikoloz Basilashvili to reach the second round on Monday.
The 17-times Grand Slam champion shone under the lights of Rod Laver Arena to wrap up the match in an hour and 12 minutes, putting on a clinic of clean hitting.
Federer struck 31 winners in the one-sided rout to preserve his perfect record of surviving the opening round at the year's first Grand Slam.
The Swiss world number three will next play Ukraine's Alexandr Dolgopolov.
Fifth seed Maria Sharapova breezed into the second round after defeating Japan’s Nao Hibino 6-1, 6-3.
World No 1 and defending champion Novak Djokovic marched imperiously into the second round with a dominant 6-3, 6-2, 6-4 victory over Chung Hyeon.
The 28-year-old Serb looked as untroubled by the Melbourne heat as he was by the South Korean teenager in the 115-minute contest, charging around Rod Laver Arena and rattling off 40 winners.
World number 51 Chung showed he had some impressive weapons at his disposal, particularly in the opening set, but was not always able to convert his best shots into points.
The 19-year-old stalled Djokovic's progress in an absorbing fifth match of the second set, holding serve after eight deuces, but the five-times champion soon advanced to a second round date with French teenager Quentin Halys, who beat Croatia's Ivan Dodig 6-4, 6-7(4), 6-4, 7-5.
Kazakhstan's Yulia Putintseva pulled off the first big upset at the Open, defeating former world No 1 Caroline Wozniacki.
Putintseva won a marathon second set to beat the Dane 1-6, 7-6, 6-4 at Hisense Arena, and advance to the second round.
This is the first time the 16th seed was ousted in the first round of the Australian Open.
Meanwhile, seventh-seed Kei Nishikori also advanced to the second round after beating Philipp Kohlschreiber of Germany 6-4, 6-3, 6-3.
Defending champion Serena Williams reached the second round after a tense 6-4, 7-5 win over feisty Italian Camila Giorgi in her first tour match in four months.
The world number one had barely played any competitive tennis since her US Open exit last September and entered a sweltering Rod Laver Arena with doubts over her fitness to face the highest-ranked unseeded player in the draw.
The slight but hard-hitting Giorgi conceded a 4-1 lead early but steadied to give the American a genuine test and Williams's roars of frustration underlined the growing tension as the match progressed.
However, it was Giorgi who wilted at 5-5 in the second set, a double-fault handing Williams the decisive break and allowing the American to close out the match with a barrage of booming serves.
In other women's matches, Chinese qualifier Wang Qiang stunned 24th seed American Sloane Stephens 6-3, 6-3.
Stephens was a semi-finalist at the Open in 2013.
Stephens, who also fell at the first hurdle last year, came into the tournament on the back of claiming her second WTA tour title at the Auckland Classic this month.
The 102-ranked Wang will next play Germany's Anna-Lena Friedsam, who floored Spain's Lourdes Dominguez Lino in three sets.
World No 4 Agnieszka Radwanska of Poland defeated the USA's Christina McHale 6-2,6-3 to advance.
