Serena Williams clinched a record 23rd grand slam title at the Australian Open on Saturday but spent most of the immediate aftermath talking about her older sister Venus.

The 35-year-old American clinched her seventh Melbourne Park crown with a 6-4 6-4 victory over Venus to surpass Steffi Graf as the most prolific grand slam title winner of the open era.

In an emotional presentation on Rod Laver Arena, seven-times grand slam champion Venus made clear her pride in her younger sister and Serena, whose victory ensures she will return to number one in the world, repaid the compliment.

"She's my inspiration and the only reason the Williams sisters exist," she said.

"There's no way I would be at 23 without her, there's no way I would be number one without her.

"She's the only reason I'm standing here today so thank you Venus for inspiring me to be the best player I could be and inspiring me to work hard."

Serena said the quality of Venus's play rather than nerves at playing her sister in a grand slam final for the ninth time were responsible for her uncharacteristically giving up two service breaks in a topsy-turvy opening set.

"She's the toughest player I've ever faced," Serena added.

"The fact that she is so good makes it that much harder. I felt like she knew where I was going to be, she was there before I hit the shots, and it was really difficult.

"I think the only really thing that changes the dynamic is because she's great, she's a great player.

"I was out there just relying on heart and fight. That's all I could really do today and it paid off."

After a single service break secured the second set and the victory for Serena, she slipped on a custom-made pair of Air Jordan shoes with 23 - also the number worn by basketball great Michael Jordan - embossed on the side.

"I finally made it to Jordan status at 23," she said.

Alexis Ohanian, Serena's fiance and co-founder of social news website Reddit, was in the stands watching the match and Tweeted of his pride at her achievement.

Serena said that having got the 23rd grand slam crown in the bag, she could now turn her thoughts to organising the wedding.

"Bridesmaids, Venus and my sisters," she said. "I really don't want to talk about it until February. I still have a couple more days. I'll take my time. It was good, now I have to think about that."