MELBOURNE, AUSTRALIA -- Australian Open tournament director Craig Tiley defended the decision to hold qualifying matches this week even though Melbourne's air quality was among the worst in the world because of smoke from wildfires devastating parts of the country.

The tournament has drawn criticism from players for contesting matches in conditions that led one, Dalila Jakupovic, to collapse to her knees while coughing heavily, and another, Bernard Tomic, to seek medical attention because of trouble breathing.

Tiley said Thursday the conditions were under a threshold set after Australian Open organizers consulted with with sports and medical experts, and scientists from the Environmental Protection Authority.

"Our medical team were satisfied with the conditions that the players were competing in, per all of the research and the data and the science that they have," Tiley said.

He said matches would have been stopped if medical staff at Melbourne Park decided it was too unhealthy to keep playing.

"Absolutely, we understand the anger, (but) a lot of it comes from the confusion and the complexity of understanding what goes on," Tiley said. "We've invited the players ... to come in at any time to have a conversation.

"If anyone at any time is feeling not well, we have a full medical team. We have a respiratory specialist on hand to deal with any of these issues."

Qualifying matches were delayed for an hour on Tuesday and two hours on Wednesday until smoke and haze from the regional wildfires cleared enough to allow play to proceed. Rain late Wednesday improved the air quality in Melbourne.

British player Liam Broady was critical Thursday of the playing conditions he dealt with Tuesday in a 6-3, 6-0 qualifying loss to 131st-ranked Ilya Ivashka of Belarus.

"The more I think about the conditions we played in ... the more it boils my blood," Broady posted on Twitter. "We can't let this slide. The email we received yesterday from the ATP and (Australian Open) was a slap in the face, conditions were 'playable'. Were they healthy?"

Broady, who finished last year ranked No. 240, said people in Melbourne were advised to keep their pets indoors on the day he played, "and yet we were expected to go outside for high intensity physical competition?"

On Wednesday, Canadian qualifier Brayden Schnur was critical of officials after his first-round win over Sebastian Ofner, and said stars such as Roger Federer and Rafael Nadal should be more outspoken about playing conditions.

The ATP player council is set to meet before the Australian Open, which begins Monday.