By JOHN PYE AP Sports Writer
Some of the so-called true blue courts at the Australian Open were coated in red after a rain front that lashed Melbourne overnight pushed through a dust storm from the northwest and left its mark on the city and the tournament.
Crazy weather has plagued the season-opening major at Melbourne Park and caused yet more disruptions on Day 4, when two-time major winner Garbine Muguruza had to wait for the roof to be closed on Rod Laver Arena before completing her 6-3, 3-6, 6-3 second-round win over Ajla Tomljanovic.
Muguruzu said as well as having a "tough battle to the end," against her Australian opponent, she had to concentrate on staying patient with all the changing weather conditions.
Smoke from devastating bushfires on Australia's east coast caused air quality in Melbourne last week to be ranked among the worst in the world, and impacted qualifying for the season's first tennis major. Heavy rain on three of the first four days of the tournament has caused more difficulties for players and organizers. On Day 3, a blustery wind made conditions difficult.
On the plus side, there are three stadiums with retractable roofs, so the show court matches will proceed.
In the other completed singles matches Thursday, sixth-seeded Belinda Bencic and Donna Vekic advanced to the third round.
U.S. Open semifinalist Bencic beat 2017 French Open champion Jelena Ostapenko 7-5, 7-5, and 19th-seeded Vekic had a 6-4, 6-2 win over Alize Cornet.
"First it was sunny, almost raining, windy," Bencic said. "You just have to accept it and try your best to adapt."
Heavy morning showers delayed play on all outside courts. That combined with the dust left a layer of red on some outside courts, making them unplayable in the morning.
Melbourne Park staff used high-pressure hoses to clean court surfaces. Light rain became heavy in the early afternoon, forcing the suspension of the only two matches that had started on outside courts.
The Australian Broadcasting Corp said the "dirty rain" from the overnight downpour had forced public pools to close and left some cars with the appearance of having been "sprayed with mud".
Bureau of Meteorology senior meteorologist Richard Carlyon told the ABC the brown rain was the result of dust storms, not bushfire smoke.
In showcourt matches scheduled later Thursday, top-ranked Rafael Nadal was playing Federico Delbonis and Nick Kyrgios was set to play Gilles Simon.
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