For the second time in just three days, the Australian Open has been rocked by a medical emergency on a main court.
Ana Ivanovic's match against qualifier Anastasija Sevastova on Rod Laver Arena was delayed after a female patron fell down the stairs in the top tier of the stadium.
With Ivanovic up a break and leading 4-3 in the first set, the match was halted for more than 20 minutes as the spectator was tended to by medical staff.
Ivanovic stopped immediately when she heard the "really loud" fall and said it left her shaking.
"Maybe it's not a good tendency to think of the worst, but it just really didn't sound so good," she said.
"So I just hope the lady was fine. It was actually good that we had to wait a little bit because I was really shaking because I could imagine (what happened) was not so nice and then they told us she was bleeding. I hope she's well."
Sevastova added: "The sound was quite frightening. And then you don't see anything from down (on court) so you don't know what happened. It was tough.
"I hope she's ok... The supervisor said to me it's serious."
The Herald Sun reported St John's Ambulance officials were waiting for a spinal board and collar to arrive before they could move the patron from the stadium during the delay.
"A patron fell on the steps inside Rod Laver Arena at 11.35am," Tennis Australia said in an official statement.
"A health professional in the crowd responded immediately followed quickly by the event first aid team.
"Additional precautions were taken before moving the patron to avoid further injury.
"The patron was stretchered to the first aid post for observation and further treatment."
There was no word on her condition, although an official said she was conscious.
A number of people claiming to be inside the stadium posted on social media to say the spectator fell down the stairs, making a loud thud.
Very little information was given to the players and fans as to when the match would continue. The players were described as appearing "terrified" by onlookers.
After 20 minutes, the players were informed by the match referee it would take at least another 10 minutes to move the injured spectator and were told to return to the locker room.
"It will be another 10 minutes at least" an Australian Open official said.
But just as they left the court, they were told to come back as the spectator was transported.
Both payers were given a three minute warm up after the delay.
On Tuesday, play was halted during a dramatic moment in Bernard Tomic's first-round match against Denis Istomin, when a female spectator required emergency medical treatment.
People sitting nearby shouted for an EpiPen, which is used to treat life-threatening allergic reactions, and a fan in the upper part of Hisense Arena responded by tossing one to another spectator, starting a chain reaction of passes until it finally reached the woman in distress.
Paramedics arrived within minutes of the woman being treated and she was helped into a wheelchair and escorted from the arena to a huge round of applause from the crowd.
Tomic and Istomin looked on with concern before they were able to resume the match in the first game of the fourth set. Tomic won the match 6-7 (4-7) 6-4 6-4 6-4.
"Potentially someone's dying and we're not sure what's going on," Tomic said in a post-match interview.
"At one stage I was looking directly at the lady. It was not a good moment to be in."
"At the end of the day, tennis is tennis, sport is sport. But if someone passes out or on dies on a tennis court, it can be very, very bad."