Tennis stars have pledged to donate $200 for every ace they serve during the summer campaign to the bushfire appeal.
The donation drive was launched by Nick Kyrgios and was quickly followed by other legends.
So far, fellow Aussies Alex de Minaur, John Millman and Sam Stosur have promised to donate the same amount of money for every ace.
Since his career began Kyrgios has successfully served a whopping 3,375 aces in singles matches, so he could be in for pledging a lot of money over the summer of tennis.
This isn't the first time Sam Stosur has done this either; in 2011 she pledged $100 for every ace when Queensland was hit by devastating floods.
The ATP Cup, which will be the first tournament of 2020, will also put forward $100 for every ace that anyone serves during the matches.
It has released a statement saying: "Each ace served across the 10-day tournament at all three venues will deliver to the Australian Red Cross bushfire disaster relief and recovery efforts.
"With more than 1500 aces expected to be served by singles and doubles players across both the group rounds and final eight in Sydney, the ATP Cup contribution is expected to exceed $150,000."
Tournament director Tom Larner added: "Most of the players are already keen to score aces and win a quick point, and having the chance to raise money for the bushfire appeal will give them that extra bit of motivation.
"As a sport we also believe it's important to recognise the tremendous contribution made by our volunteer firefighters, emergency services workers and community volunteers who come from every walk of life.
"We know many of them are also members of our tennis family and this initiative is just one way we can acknowledge their selflessness and bravery."
The tournament gets underway today at Sydney's Ken Rosewall Arena.