Sydney's smoky haze continues to plague the Australian Open golf championship, with former winner Matt Jones claiming he'd never endured anything like it and one player even resorting to wearing a surgical mask.
Jones snared the early clubhouse lead with a first-round four-under-par 67 before saying Thursday's visibility and comfort levels were among the worst he'd endured.
"It's awful," Jones said.
"I'm not sure what the forecast is but the smoke's not good at all.
"It's tough to see your golf ball when you're out there playing, where it finishes.
"Your eyes do burn up. I've got that cough like you've got something in your lungs, phlegm in your lungs or whatever, but yeah it's not fun.
"I hope my kids are inside in the hotel room."
With sporting events cancelled across Sydney this week as bushfires continue to rage all over NSW, children, the elderly and those with heart and lung conditions are most at risk.
Health authorities have advised people to reduce outdoor activities and seek medical advice if they experience difficulties.
New Zealander Ryan Chisnall, an asthmatic, covered up with a mask as conditions deteriorated on Thursday afternoon.
Golf Australia boss said Stephen Pitt promised pre-Open to have ample medical staff on site at The Australian and they certainly had their hands full.
St John Ambulance officials reported one asthma attack and "plenty" of people complaining of sore throats, stinging eyes, wheeziness and even ash in their eyes.
"It got pretty thick for a while and still is. It's not great," former world No.1 Adam Scott said after struggling to a four-over 75 start.
"On Tuesday the first day I got here my eyes were stinging. I was joking that I need a cleanse but I should shove some salt water up my nose or something and try rinse myself out.
"Not the conditions we want to be playing in; kind of hope for rain. I don't know what we can do."
Tournament director Trevor Herden was hoping forecast sea breezes would help clear skies by the weekend.
"Even when I played in China, I didn't think it was like this at all," Jones said.
"Definitely not in Malaysia. It's just unbelievably humid (there).
"I've never experienced something like this."
Fellow US PGA Tour star Cameron Smith, a member of Ernie Els' International team, hoped the challenging conditions wouldn't take too much of a toll ahead of next week's Presidents Cup at Royal Melbourne.
"It's a bit odd, isn't it, but what can you do?" Smith said after posting a three-under 68 to trail the leaders by three shots.
"I haven't really felt any different, it's just kind of the look.
"But we'll see after the four days, it might take a bit out of everyone, I'm sure."