Her $43,000 champion's earnings will go to Australian bushfire relief. (Getty Images)

Serena Williams not only won her first title since 2017, but she also donated all of her prize money to Australia bushfire relief.

The 38-year-old beat Jessica Pegula, 6-4, 6-3 in the Auckland final, winning the WTA International for her 73rd career title. 

In her acceptance speech, she revealed her donation plans for her $43,000 in earnings.

"So much has happened," Serena said. "So I decided at the beginning of the tournament every match I played I'd donate a dress and I'd also donate all my prize money for a great cause."

The title marks Serena's first since winning the 2017 Australian Open. She has now won a title in four decades, and it's her first trophy since giving birth to her daughter Olympia. 

"I've been waiting two years for this moment!" she said, though technically it has been three.

The American needed a new tradition to start the decade off with, and went with a cartwheel. 

 
 
 
 
 
 
 
 
 
 
 
 
 

Flipping to Melbourne. Thanks @jarmere #rockstarrpartner

A post shared by Serena Williams (@serenawilliams) on

She and Caroline Wozniacki would fall in the doubles final to Asia Muhammad and Taylor Townsend.