Tennis great Serena Williams was among the first to congratulate Caroline Wozniacki after the Dane succeeded her as Australian Open champion.
In the absence of 2017 winner Williams, who opted not to defend her title in Melbourne after giving birth in September, Wozniacki defeated Simona Halep 7-6 (7-2) 3-6 6-4 to claim the first grand slam crown of her career.
It had appeared the 27-year-old, who first rose to number one in the world rankings in 2010, would struggle to fulfil her promise as her wait to capture a major dragged on.
She arrived at last year's tournament as the 17th seed and lost in the third round, but will now displace Halep at the summit of the rankings thanks to her triumph on Rod Laver Arena, prompting her friend Williams to send a message acknowledging Wozniacki's achievement.
Williams wrote on Twitter: "I got too nervous to watch but woke up to @CaroWozniacki new number one and aussie open champ. So awesome. So happy. Are those tears? Yup they are... from a year ago to today I'm so proud my friend so proud. Literally can't even sleep now."
I got too nervous to watch but woke up to @CaroWozniacki new number one and aussie open champ. So awesome. So happy. Are those tears? Yup they are. from a year ago to today I'm so proud my friend so proud. Literally can't even sleep now
-- Serena Williams (@serenawilliams) January 27, 2018
Informed of Williams' message as she was interviewed after her victory, Wozniacki replied: "I love you Serena."
Rod Laver, Australia's 11-time grand slam singles champion, tweeted to say: "Congratulations @CaroWozniacki - welcome to the Club."
Congratulations @CaroWozniacki - welcome to the Club.-- Rod Laver (@rodlaver) January 27, 2018
Kasper Schmeichel, Wozniacki's compatriot and a Premier League winner with Leicester City in 2015-16, also used social media to praise the first Danish grand slam champion.
He wrote: "What a final! Huge congratulations on your first Grand Slam title @CaroWozniacki."