One player, Dalila Jakupovic of Slovenia, was forced to retire from her match at 6-4, 5-6 against Swiss Stefanie Voegele when she sunk to her knees with an episode of uncontrollable coughing.
"I was really scared that I would collapse," Jakupovic told reporters after the match.
"I just couldn’t breathe anymore and I just fell on the floor. It’s not healthy for us."
Canada's Eugenie Bouchard required medical assistance before completing a three-hour match and certain players are unhappy with the tournament organisers.
World number five Elina Svitolina wrote on Twitter: "Why do we need to wait for something bad to happen to do an action."
Frenchwoman Alize Cornet added: "This is not reasonable."
A thick haze of smoke developed overnight in Melbourne due to the raging bush fires that have claimed at least 27 lives in Australia.
The air quality reached "hazardous" on a warning scale of six levels and was described as "the worst in the world" by Victoria State Cheif Health Officer Brett Sutton.
Australian Open organisers do have air quality procedures in place for players including the use of eight indoor courts at Melbourne Park with air monitoring equipment installed to detect any danger.
"This is a new experience for all of us in how we manage air quality, so we have to listen to the experts," Australian Open tournament director Craig Tiley said.
The Australian Open main draw begins on January 20. - dpa/Asian News Network