Melbourne - Alexander Zverev renewed a pledge on Wednesday to donate the A$4.12 million ($2.83 million) Australian Open winner's cheque to bushfire relief if he lifts the title, after sweeping into the semi-finals.
The generous 22-year-old German has already raised $50 000 by handing over $10 000 for each match he has won at Melbourne Park, a vow made after his first-round victory.
At the same time, he said he would also donate the winner's earnings should he break through for a maiden Grand Slam title
"Yes, it is still true. I hope I can make it happen," he told cheering fans on Rod Laver Arena after sweeping past veteran Swiss Stan Wawrinka 1-6, 6-3, 6-4, 6-2 in the quarter-finals.
"I made the people of Australia a promise. I will keep that promise if it happens.
"Four million Australian dollars would be nice. But there's people that need it... for rebuilding the lives they once knew.
"It is much more important that they get that money," he added in an on-court interview with John McEnroe.
Fires have ravaged large parts of Australia, leaving 33 people dead and thousands of homes destroyed, with sports stars around the world rallying to support recovery efforts.
It was feared that smoke from the blazes could impact the opening Grand Slam of the year after qualifying was hit by thick smog.
But rain helped douse some of the fires and the air quality in Melbourne has not affected the tournament.
For Zverev to make good on his pledge he will need to first get past either world number one Rafael Nadal or fifth seed Dominic Thiem in the semi-finals.
If he can do that, seven-time champion Novak Djokovic or six-time winner Roger Federer await in the final.
Zverev's run to the last four in Melbourne is the farthest he has got in the 19 Grand Slams he has played.