Britain’s Liam Broady has described an email sent to players defending the decision to allow play at the Australian Open despite the poor air quality as a “slap in the face”.

He says it “boils his blood” that he was made to play his first-round qualifying match on Tuesday.

The 26-year-old was “gasping for air” as he lost to Belarusian Ilya Ivashka.

Play had earlier been suspended for an hour as Melbourne was blanketed in smoke from the bushfires.

The email was sent to male players by the ATP Tour and Tennis Australia, and has been seen by BBC Sport.

It concludes the “conditions are challenging, but the medical experts say they are acceptable for play”.

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In a post on social media earlier on Thursday, Broady outlined his concerns.

“The more I think about the conditions we played in a few days ago, the more it boils my blood. We can’t let this slide.

“The email we received yesterday from the ATP and AO was a slap in the face. Conditions were ‘playable’. Were they ‘healthy’?

“Citizens of Melbourne were warned to keep their animals indoors the day I played qualifying, and yet we were expected to go outside for high-intensity physical competition?

“What do we have to do to create a players’ union? Where is the protection for players, both male and female? On tour we let so many things go that aren’t right but at some point we have to make a stand. ALL players need protection not just a select few.”

Slovenia’s Dalila Jakupovic was forced to retire from her qualifying match after a coughing fit and says other players she spoke to reported breathing difficulties and headaches.

The email to ATP members said “player welfare is utmost in our considerations”, and details the hitherto undisclosed protocols that Tennis Australia has put into place.

A ‘PM2.5’ air quality reading is being taken every four minutes at Melbourne Park. Whenever the reading exceeds 200, Tennis Australia says play is suspended.

Readings elsewhere in the city on Tuesday suggested the air quality index was over 200, but the email says “no play has taken place at any time above the 200 threshold on the PM2.5 scale”.

It also claims some sporting organisations have a threshold of 300 before they take any decision to suspend play.

There were no problems with air quality as qualifying continued on Thursday. Wednesday’s heavy rain has brought in cooler conditions, with Melbourne’s air officially rated as “good”.

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‘A lot are saying they can’t wait to get out of Australia right now’

American player Noah Rubin, who lost in the first round of qualifying on Wednesday, said a lot of players felt “disrespected” by the email, which he described as being sent “too late”.

Former Wimbledon junior champion Rubin, 23, says he had “blood and black stuff” coming out of his nose after his match, also complaining of irritated eyes and shortness of breath.

“A lot of players have been feeling it in the throat and eyes,” Rubin, who was not the source of the leaked email, told BBC Sport. “It can’t be healthy breathing it in.

“The talk between players is about disappointment. A lot are saying they can’t wait to get out of Australia right now and we love playing in Australia.

“It’s left a bad taste in a lot of people’s mouths – almost literally.

“We feel awful about what is happening with the fires – it is terrible and obviously there are way worse things – but we’re talking about how are we having a tournament going on, and how do we not know how to go about it? Why can’t we play inside; why are there not emergency things taking place?”

Rubin added he had approached Tennis Australia and the ATP for clarity, accusing them of being defensive when he asked for more communication to be given to the players about why decisions had been made.

American player Nicole Gibbs, who was treated for a mouth cancer last year and had two months out following surgery, urged tournament officials to display the air quality numbers in the players’ locker rooms.

“We should have access to the air quality numbers and the associated health risk of whatever that valuation is,” said Gibbs, who lost to Britain’s Harriet Dart in qualifying on Thursday.

“We have TVs in our locker room which show us what the heat index is at any time so I’ve been expressing to tournament officials I’d also like to see the air quality.”

Hear more from Nicole Gibbs on 5 live Sport from 19:00 GMT on Thursday

Coughing fits, retirements and player anger – this week’s Australian Open qualifying has been repeatedly affected by the country’s ongoing bushfire crisis.

So how does the “very poor” air quality affect elite athletes?

Professor of sport and exercise science John Brewer explains.

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The quick science bit

When we exercise and we take air into our lungs, there are minute sacks in our lungs called alveoli. They extract oxygen from that air and take that into the blood stream and then into the muscles to help provide the body with the energy it needs.

If that air going into their lungs is contaminated with other particles from the bush fires, then that can really impact on the ability of the sacks to transport the all-important oxygen into the blood stream.

For tennis players, that can cause extra fatigue, perhaps the loss of concentration, plus headaches and nausea, as well as slow their recovery rate afterwards.

The numbers

At rest, most people will breathe in, and out, around 10 litres of air per minute.

Just under 21% of this consists of oxygen.

During exercise this demand for energy, oxygen and air increases significantly, and in a sport such as tennis where players need to perform repeated bursts of high-intensity activity, the amount of air going into and out of the lungs can often approach 100 litres per minute, a 10-fold increase.

What about players with asthma?

For players who have pre-existing conditions such as asthma, the irritation caused by the particulates in the air could trigger a reaction that narrows the airways, and makes breathing and oxygen uptake even harder.

In some cases this could prevent them from playing altogether, causing significant respiratory distress, which if untreated could pose a risk to the player.

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Don’t forget the heat

High levels of heat and humidity are a routine challenge for players at the Australian Open, and will result in higher heart rates and breathing frequency as players cope with the physiological demands of keeping cool and preventing their body temperature from rising too high.

In those conditions, the heart has to work much harder to pump blood to the skin so that body heat can be lost, and this extra load on the heart will be even greater when air in the lungs is of a poor quality.

Players will find themselves fatiguing rapidly as they cope with a lack of oxygen in the blood, and the high heart rates they will experience as the body combats the effects of heat and dehydration.

Any longer-term impact?

The poor air quality and smoke particles will affect spectators as well as players, and some of the air quality levels that have been recorded equate to smoking large numbers of cigarettes a day.

As well as restricting breathing and oxygen transport capacity, prolonged exposure to smoke-polluted air is almost certainly going to impact on the health of the general population, with the potential for harmful chemicals and particulates to enter the lungs and cause long-term damage.

Spectators who are concerned should be advised to wear face masks that will help filter the harmful particulates from the air that they breathe in.

Australian Open organisers are confident the tournament will start and finish on time despite continuing health concerns over Melbourne’s air quality from bushfires in the country.

Some players have complained about having to play qualifying matches in smoky conditions.

“There is a lot of speculation about the Australian Open not happening, or starting later,” said tournament director Craig Tiley.

“The Australian Open is happening.”

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Slovenia’s Dalila Jakupovic had to be helped off court when she retired from her qualifying match on Tuesday because of the “unhealthy” air quality.

British player Liam Broady said having to play his first-round qualifier on the same day “made his blood boil”, adding he was “gasping for air” as he lost to Belarusian Ilya Ivashka.

People in Melbourne were advised to stay indoors and keep pets inside on Tuesday.

A number of players have also criticised the tournament for not postponing the matches, with American Noah Rubin saying he had “blood and black stuff” coming out of his nose following his match on Wednesday.

Tiley says he understands the anger of the players, adding he believes it stems from the confusion of seeing different measurements of air quality depending on the app or website they used.

Rubin, a former Wimbledon junior champion, also told BBC Sport he was unhappy with the communication from tournament officials, saying they were reluctant to explain the figures to the players.

“Air quality is a very complex and confusing issue which relates to a number of different factors,” said Tiley.

“There are number of different air quality measures and it is made more complex by going on an app. There are different apps and websites which give you different readings.

“This is about trusting the medical advice and trusting the expertise and scientific advice of the people who analyse this every day.

“The safety, the wellbeing and the health of the players is the priority for us, as with our staff and our fans.”

Tiley said the tournament decided to use a ‘PM2.5 concentrate’ measure to monitor the air quality levels after receiving advice from environmental and medical experts.

A PM2.5 reading is being taken every four minutes at Melbourne Park. If the reading exceeds 200, Tiley said it would be deemed hazardous and play would be suspended.

He says no reading has exceeded the 200 mark while matches have been in progress at Melbourne Park. However, it did exceed that mark – rated as ‘very unhealthy’ – on Tuesday, when qualifying was delayed by an hour.

If play is suspended, the Tennis Australia chief executive says the tournament will continue indoors under the roofs on Rod Laver Arena, Margaret Court Arena and Melbourne Arena.

“We do have three indoor arenas in which we can compete. It may look differently but the tournament will happen,” Tiley said.

“We are speculating if that would happen but if we had to work it out we would.

“We don’t expect that to happen because we haven’t yet seen anywhere in the world where there has been above that 200 on the PM2.5 concentrate consecutively over two weeks.”

The first Grand Slam of the year gets under way on Monday.

Hear more from Craig Tiley on 5 live Sport from 19:00 GMT on Thursday

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British number three Harriet Dart reached the third round of Australian Open qualifying with a straight-set win over American Nicole Gibbs.

The 23-year-old world number 169 won 6-2 6-3 and faces Italy’s Giulia Gatto-Monticone for a place in the main draw.

However, fellow Briton Samantha Murray Sharan, 32, lost 2-6 6-4 6-4 in the opening round to China’s Yue Yuan.

Canada’s Eugenie Bouchard also reached the third round with a 6-3 6-1 victory over Australia’s Maddison Inglis.

The former Australian Open semi-finalist will play Italian Martina Trevisan next.

In the men’s draw, Belgian Steve Darcis played the final match of his career in a first-round defeat.

The 35-year-old, who beat Rafael Nadal in the 2013 Wimbledon first round, lost 7-5 7-5 to France’s Elliot Benchetrit.

“A wonderful page in my life turns,” said Darcis on Twitter following his exit.

“Thank you all for your support and thank you also to those who by demolishing me made me stronger.”

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British number two Heather Watson made it through to the semi-finals of the Hobart International with a 6-7 (5-7) 6-4 7-5 win over Elise Mertens.

Following a rain delay at 4-4 in the second set, Watson broke the Belgian and held serve to level the match.

There were seven breaks of serve in the third set, with the decisive one coming when Watson went 6-5 up.

The 27-year-old held serve for victory in three hours 33 minutes to progress in an event she won in 2015.

During the match, the draw for the Australian Open, which will take place between 20 January and 2 February, took place and Watson, ranked 101st in the world, will play Czech world number 62 Kristyna Pliskova – twin sister of second seed Karolina – in the first round.

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American teenager Coco Gauff will again face Venus Williams in the first round of a Grand Slam after the pair were drawn together at the Australian Open.

Gauff, 15, announced her arrival on the biggest stage by beating 39-year-old Williams, a seven-time Grand Slam singles winner, at Wimbledon in July.

Britain’s Johanna Konta, seeded 12th, will play Tunisia’s Ons Jabeur.

In the men’s draw, British 30th seed Dan Evans meets American Mackenzie McDonald in Melbourne.

Evans, 29, is playing in his first Slam as Britain’s leading male player and could face Serbia’s defending champion Novak Djokovic in the third round.

Djokovic, who is aiming for a record-extending eighth title, does not have the easiest opener after being drawn against Germany’s world number 37 Jan-Lennard Struff.

The first Grand Slam of the year begins on Monday.

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Swiss great Roger Federer has been drawn in the same half as second seed Djokovic, meaning the pair could meet in the semi-finals.

Federer, 38, starts against American Steve Johnson and has a favourable-looking draw, although Bulgaria’s Grigor Dimitrov – who memorably beat the Swiss in the US Open quarter-finals in September – and Canada’s exciting talent Denis Shapovolov are potential opponents before the quarter-finals.

Spanish top seed Rafael Nadal plays against Bolivia’s Hugo Dellien in the first round, with the possibility of a blockbuster fourth-round match against Australia’s Nick Kyrgios.

The pair have not always seen eye-to-eye and met in a dramatic second-round match at Wimbledon last year, where Kyrgios tried to rattle Nadal with constant complaints about the Spaniard’s slow play.

British number two Cameron Norrie plays Frenchman Pierre-Hugues Herbert in his opening match, while Kyle Edmund – who reached the semi-finals in Melbourne two years ago but has dropped to 69th in the world – has a tough opener against Serbia’s 24th seed Dusan Lajovic.

Russian fourth seed Daniil Medvedev, looking to win his first Grand Slam after reaching the 2019 US Open final, has been pitched against dangerous American floater Frances Tiafoe, who reached the quarter-finals last year.

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British duo Dan Evans and Kyle Edmund were both beaten at the quarter-final stage of different warm-up events for the Australian Open.

Evans got to the last eight of the Adelaide International before losing 6-4 3-6 6-3 to Russian Andrey Rublev.

Edmund suffered a 7-6 (7-5) 7-6 (7-5) defeat by American John Isner at the Auckland Classic in New Zealand.

Isner’s serve was key as he sent down 25 aces during the match and had a first-serve percentage of 75%.

The Australian Open – the first Grand Slam of the year – takes place between 20 January and 2 February.

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