In a world first, a Sydney surgeon has used the radical method in a transplant operation, which has won him international accolades.
Dr Albert Shun, from The Children's Hospital at Westmead, used the unorthodox approach when confronted with a medical problem while operating on the two-year-old.
Born with biliary artresia, Mackenzie, from Canberra, needed the life-saving operation earlier this year.
But after inserting a portion of the adult-size liver in the little girl, Dr Shun discovered it was too big and was placing pressure on her blood vessels which could have been fatal.
Having heard about the use of ping-pong balls in operations overseas, he decided to test their suitability in transplant surgery.
"I rang my wife and asked her to go to Big W and buy me some ping-pong balls," he said.
"I was using a sponge as a back-up purpose but there was no way I could close her up the way it was.
"She is the first (transplant patient) in the world that the ping-pongs have been used for these purposes."
In Mackenzie's case, the ball keeps the liver off the arteries. Since Mackenzie's operation, Dr Shun and his team have performed the procedure several times.
However, the ball has only remained in the patients for a few days to allow the swelling to reduce after the transplant.
Dr Shun said Mackenzie's liver would grow around the ball without causing an infection.
"There shouldn't be any complications. We are in a unique situation in Australia because we have a low donor rate so we have to be adaptable," he said.
Unaware she has a foreign object inside her body, little Mackenzie is now running around like every toddler her age.
Her parents Letice Darswell and Guy Argaet are thrilled their daughter is well after she was so seriously ill from birth.
"We didn't get told about the ping-pong until after the operation," Ms Darswell said.
"It was a shock when (Dr Shun) came out of surgery."
Biliary artresia is a rare gastro-intestinal disorder in newborns where the ducts that carry bile from the liver to the intestine are destroyed. Mackenzie's liver became so scarred that she began to develop cirrhosis and needed a transplant."She is so normal now. She is a happy kid," Ms Darswell said