Alexander Zverev is two wins away from handing over $4.12 million to Australia’s bushfire relief campaign after storming into his maiden grand slam semi-final.

The German recovered from a dire start to see off three-times major winner Stan Wawrinka 1-6 6-3 6-4 6-2 in their Australian Open quarter-final on Wednesday.

Touted years ago as tennis’s next big thing, Zverev had never previously made it past the fourth round at Melbourne Park.

His only two quarter-final runs at a major both came on clay at Roland Garros.

“You guys can’t imagine what this means to me. I hope this will be the first of many,” the 22-year-old said.

“It feels awesome. I don’t know what to say. I mean, I’ve done well in other tournaments. I’ve won matches, but I never could break that barrier in a grand slam.”

After after suffering from a serious bout of the summer serving yips, Zverev arrived in Melbourne on the back of three straight losses at this month’s ATP Cup.

After battling through his Open opener against Marco Cecchinato, the out-of-sorts world No.7 pledged to donate his entire winner’s cheque to the bushfire victims if he won the Open.

And now he’s standing by it.

“I hope I can make it happen,” Zverev said.

“I made the people of Australia a promise, I will keep that promise if it happens.

“I always said I’m not a money-driven person. My parents always taught me with money you should achieve things that help others and help the people that actually need the money and for me, right now.”

He still has a way to go.

Zverev must overcome either world No.1 Rafael Nadal or fifth seed Dominic Thiem in Friday night’s semi-final and then Novak Djokovic or Roger Federer in Sunday’s championship match.