Nadal, Tsitsipas, Cilic, Federer, Sharapova, Wozniacki, Kvitova register 1st round wins

MELBOURNE, Jan 14 (AFP): A ruthless Rafael Nadal showed no mercy in a clinical first round thumping at the Australian Open Monday with fellow former champions Caroline Wozniacki, Angelique Kerber and Maria Sharapova also romping through.

The Spanish 17-time Grand Slam winner, who cut short his 2018 season to have surgery on a foot injury, cruised into round two of the year's opening major 6-4, 6-3, 7-5 against Australian wildcard James Duckworth.

Fifth seed Kevin Anderson progressed, as did NextGen Finals champion Stefanos Tsitsipas. An aggressive Tsitsipas became on Monday the first Greek man to win a match at the Australian Open after battling back from a set down to beat Italy's Mario Berrettini in four tough sets.

But ninth seed John Isner became the first top seed to crash out.

World number three Wozniacki, who made her Grand Slam breakthrough in Melbourne last year, opened her defence with a convincing 6-3, 6-4 win over Belgium's Alison van Uytvanck.

Second seed and 2016 champion Angelique Kerber was also impressive, sweeping past Slovenia's Polona Hercog 6-2, 6-2.

Sharapova, a winner at Melbourne in 2008, signalled her intent with a rare 6-0, 6-0 double bagel demolition of Britain's Harriet Dart.

Meanwhile, Last year's Australian Open runner-up Marin Cilic wasted little time in reaching the second round on Monday with a 6-2, 6-4, 7-6 (7/3) win over Australian Bernard Tomic.

Sixth seed Cilic, who lost an epic final in five sets to Roger Federer a year ago, took a shade over two hours to progress on Margaret Court Arena.

In another match, ageless Roger Federer warmed up for a run at a record seventh Australian Open title Monday by breezing past Uzbek Denis Istomin to book a spot in the second round.

The 37-year-old Swiss master made light of his assignment on Rod Laver Arena, wrapping up the match 6-3, 6-4, 6-4 as he confidently began his title defence.

Meanwhile, two-time Wimbledon champion Petra Kvitova strolled into the Australian Open second round with a straight sets win over Magdelena Rybarikova of Slovakia on Monday.

The Czech eighth seed struggled with her serve early in the match before finding her rhythm for a 6-3, 6-2 victory.

Meanwhile, gutsy Andy Murray fought to the end before losing an epic Australian Open farewell match 6-4, 6-4, 6-7 (5/7), 6-7 (4/7) at the hands of Roberto Bautista Agut Monday.