Tennis legend Margaret Court has hailed Ashleigh Barty's rise to world No.1, but says the 23-year-old now faces an even bigger challenge facing her.
On Monday, Barty became the first Australian woman to seize the world No.1 ranking since Evonne Goolagong Cawley sat on top of the pile for a fortnight in 1976.
The feat came just two weeks after Barty broke through for her first grand slam title with victory at the French Open.
Court, a winner of 24 grand slam singles titles, knows all about the pressure of being the world's best player.
Although the WTA rankings system weren't in place during Court's era of dominance, the Australian had no peers when it came to conversations about the best female player in the world.
Court was full of praise for Barty's meteoric rise, believing the Queenslander has all the physical and mental tools to succeed long term.
But she said Sam Stosur's 2011 US Open triumph proved that there were no guarantees for long-term glory.
"The challenge now is for Ash to stay there (at No.1)," Court told AAP.
"That's a real champion - to stay at the top, because you saw with Sam, she came through and she won a grand slam, and I thought she would go on and do a lot more.
"Even with the Japanese girl (Naomi Osaka) it will be interesting to see if she'll come back up. She's won a couple (of grand slams) and has played really well.
"That's when the pressure comes, when you're No.1 and you've got to stay there."
Court is a huge fan of Barty's style, saying the 166cm star's ability to play well on a range of different surfaces is a huge weapon.
"She's got that slice, and she's got that variety," Court said.
"Most of them today have one game. At least she's got a variety to change her strokes, which not a lot of players can do today.
"People used to say her height is against her. But her timing is so good. It's not about height.
"We had the Maureen Connollys that were shorter than Barty. She won three Wimbledons. It's all about timing."
Barty struggled with the pressures of elite tennis earlier in her career, prompting her to quit the sport to take up cricket.
The right-hander has since learnt to cope with the spotlight, and Court is looking forward to seeing what Barty will produce in the years ahead.
"It would be interesting to see how she takes the pressure, and she seems to be taking it well," Court said.
"She's got a good team around her, and she seems happy. That's the most important thing when you're away and travelling."