When they called, they announced Rally for Relief - a tennis fundraiser that happened to be one of the most talented events in Australian tennis history and has reportedly raised an unbelievable $ 4.8 million.
'This was definitely an incredible kick off.
The 20-year-old, who is ranked 21st, suffered a muscle tear during the ATP Cup campaign, where he played four intense matches, including a three hour-and-24-minute defeat by Britain's Dan Evans and a three-set tussle with Rafael Nadal. You wish that this doesn't happen in your country.
The 20-time grand-slam victor had also dipped into his own pocket, combining with Nadal to make a $250,000 donation, with fundraising efforts to continue during the Australian Open.
That is the opinion of Eurosport tennis expert and seven-time Grand Slam victor Mats Wilander.
American Williams, a 23-time Grand Slam singles champion, said she had taken her daughter, Olympia, to meet the firefighters.
"But these kind of team competitions are really truly special and I'm personally over the cloud with my emotions, and hopefully I can take that positive energy and use it for Australian Open".
'What I wanted to do was raise awareness, raise money and tell people to still come and travel to Australia because people probably think around the world that you can't right now, ' Federer said. "And to have some fun, have a hit with Nick ... it wasn't about winning and losing". "Now I've just got to look at what's ahead".
"The awareness has grown and I think we're doing everything we possibly can to overcome this".
The ongoing fires in Australia have killed 28 people and destroyed several thousand homes, majority in New South Wales and Victoria states.
The ATP on Sunday pledged 500,000 USA dollars to the World Wildlife Fund (WWF) Australian Wildlife and Nature Recovery Fund as part of the bushfire relief efforts.
Williams pledged the winnings from her first title victory in almost three years at the Auckland Classic.
Australian Nick Kyrgios has pledged 200 Australian dollars for every ace he hits this month.