Ash Barty could only shake her head and laugh at a funny incident during her post-match interview at the Australian Open on Thursday.
The World No.1 - sporting a heavily strapped left leg - cast friendship aside with a hard-earned win over Fed Cup teammate Daria Gavrilova that left viewers worried for the 24-year-old.
‘APPALLED’: Anger over 'disgusting' Aus Open crowd act
Barty backed up her 6-0 6-0 first-round win over Danka Kovinic with a less convincing 6-1 7-6 (9-7) victory on Thursday that thrust the No.1 seed into the last 32 for a fifth straight year.
Barty looked to be cruising towards an easy win until losing her way from 5-2 up in the second set.
She eventually regained her mojo in the second set tiebreaker, fending off a set point to Gavrilova before winning the next two points to book her spot in the next round.
Speaking to good friend and former Aussie tennis player Casey Dellacqua after the match, Barty brushed aside concerns about her strapped leg, insisting she was “fit as a fiddle”.
Dellacqua ended the interview by asking Barty: "You know it's my birthday today, right?" prompting a hilarious response from the World No.1.
Barty said she had something special planned for Dellacqua but the former tennis player ruined the surprise.
"Yeah well I was going to get everyone in here (inside Rod Laver Arena) to sing 'Happy Birthday', you've just stitched yourself up," Barty quipped.
Dellacqua jokingly talked about how excited she was to open Barty's present later on, to which the World No.1 responded: "My present is everyone singing to you now".
Barty then turned orchestrator by encouraging fans to sing to the birthday girl.
She was forced to shout, "Oh come on", when the first attempt fell somewhat flat, however.
Barty's pleas to the crowd lifted the noise levels around the stadium but there was a distinct lack of unison among the singing group, resulting in a cacophony of noise.
"OK that was an absolute shambles," Barty laughed, before signing off by wishing her mate a happy birthday.
Barty overcomes ‘worrying’ second set collapse
It was all smiles for the World No.1 after the match, but far from it at times during the second round clash against compatriot Gavrilova.
The top seed dropped serve twice while trying to close out the match, then had to save two set points in the tiebreaker before eventually prevailing after one hour and 32 minutes.
In a contest in which she appeared to be bothered by the thick strapping on her left leg, Barty coughed up six double-faults and committed 34 unforced errors.
Despite winning the Yarra Valley Classic last week in her first tournament back after almost a year out of tennis, Barty said she was still trying to find her A game.
"Obviously having 12 months off it's a little bit rusty but I'm certainly happy with how I've been able to fight though the last couple of weeks," she said.
In a rare sight in the cut-throat world of professional tennis, Barty and Gavrilova spent about an hour warming up together side by side on Rod Laver Arena on Thursday morning.
But after posing happily for a pre-match photo together at the net, Barty swiftly put her game face on.
The top seed dropped her opening service game but immediately struck back, reeling off six consecutive games to pocket the first set in 27 minutes.
The two combatants are separated by 386 spots in the rankings as Gavrilova continues a comeback from her own year-long layoff with a foot injury.
But that didn't stop Gavrilova from making Barty sweat after rattling off four games in a row to force the second-set breaker.
"When you play another Aussie, you play a compatriot, the rankings go out the window. Experience goes out the window," Barty said.
"Typically you know each other very well so it was always going to be a tricky match no matter what."
A semi-finalist last year, Barty will return on Saturday to play Russian Ekaterina Alexandrova or Czech Barbora Krejcikova for a fourth-round berth.
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