– Red dust and rain combined to give some of the blue courts at the Australian Open a more Roland Garros hue, adding yet another element to the freakish conditions that have plagued the first four days of the tournament.

Smoke from devastating bush fires on Australia's east coast caused air quality in Melbourne last week to be ranked among the worst in the world, and affected qualifying.

This week, rain on three of the first four days of the tournament has caused more difficulties for players and organizers.

Play was delayed on outside courts Thursday by more showers and what a weather expert called "dirty rain" that left red dust covering some outside courts at Melbourne Park and turned the water in the Yarra River, which winds between the tennis complex and the city, deep brown.

Melbourne Park staff used high-pressure hoses to clean court surfaces. Light rain became heavy, forcing the suspension of play on outside courts until the sun came out.

On the plus side, there are three stadiums with retractable roofs, so the show courts will go on.

Fourth-seeded Daniil Medvedev needed a medical timeout for a nose bleed before beating Spanish qualifier Pedro Martinez 7-5, 6-1, 6-3 and advancing to the third round.

His match followed sixth-seeded Belinda Bencic's 7-5 7-5 win over 2017 French Open champion Jelena Ostapenko.

Second-seeded Karolina Pliskova advanced to the third round with a 6-3, 6-3 win over Laura Siegemund following Garbine Muguruza's 6-3, 3-6, 6-3 win over Ajla Tomljanovic.