Worries have been raised over the health of players at the Australian Open, after two matches were forced to be abandoned due to the presence of heavy smoke.

During a qualifying match on 14 January, Slovenia’s Dalila Jakupovic won the first set, but then suffered a coughing fit, forcing her to retire from the contest.

Former champion Maria Sharapova was also forced to abandon an exhibition match due to the smoke.

Winds have blown smoke from the raging bushfires into the city of Melbourne – where the tournament is being held – resulting in the Environmental Protection Authority declaring air quality as being "very poor".

Following her retirement from the tournament, Jakupovic criticised the organisers and said the match "should never have been allowed to take place".

“It’s not healthy for us," she said in a press conference following the match. "I was surprised, I thought we would not be playing today."

A number of other players, including former Wimbledon finalist Eugenie Bouchard, have also been forced to call medical time-outs during their matches in order to deal with the effects of the smoke.

A number of players – including Novak Djokovic, the defending men's title champion – have suggested delaying the tournament in order to protect players' health.

The bushfires have been burning in the state of Victoria since November.