The quiet but steely Queensland-based youngster found herself the focus of attention at the All England Club on Friday after being drawn as the one to play the 23-time grand slam winner in her return to singles action after nearly four years.
The 20-year-old Joint was born, like Williams, in Michigan, before more recently switching her allegiance to her dad's home country of Australia, but reckoned it was a "dream" and an "honour" to now be the first to play the 44-year-old legend in her singles comeback.
It was in September 2022 that Williams last took to the singles court, beaten at the US Open by Ajla Tomljanovic -- and Joint's not ruling out the prospect that after Tuesday's match that it's another Australian who'll still be able to make the boast of being the last player to beat Serena Williams.
"I talked to Ajla this morning, and she gave me a little pep talk, which was nice. She told me I can beat anyone, and Serena will be just as nervous, probably, coming back in her first match at Wimbledon," Joint told a packed press conference.
"It's an honour. I always dreamed about playing Serena Williams, and if you told me 10 years ago that I'd be playing her first round at Wimbledon, that's just crazy. I have so much respect for her, she was one of my idols growing up. I never thought I'd get the opportunity to play against her.
"When I saw she'd got a wild card, there was always a part of me that wanted to experience playing against her.
"It's not something that a lot of people have been able to say they've done, so I'm just very excited for the opportunity."
But though Joint is on a wretched run after her dazzling breakthrough 2025 season, and will drop from Australian No.1 this week to No.4 by the time she plays Williams on Tuesday, the youngster who won two titles as a teenage novice last year cuts a quietly confident figure.
"I think any match is winnable," said Joint, who's lost 13 of her last 14 contests.
"Serena is still an amazing player, so I'm sure it's going to be a difficult match, but I also think that I have a chance to win."
So, who actually is the favourite here?
The greatest player of all-time who's been away for four years, and has other priorities as a 44-year-old mum-of-two? Or one of the game's rising stars, who may have hit a 'second-season slump' but is good enough to have won the prestigious Eastbourne grass-court title 12 months ago?
"It's a difficult question," smiled Joint. "I try not to think of what other people think will happen. Tennis is a crazy sport, anything can happen, just depends who's better on that day. So, we'll see on Tuesday."
Joint had to laugh when someone suggested to her all the support would be behind Williams. "Really? Not for me? What?" she laughed with mock indignation.
"I've played Madison Keys on Arthur Ashe (Stadium in New York), so I've experienced something similar before. I hope there's a couple of people in the crowd for me..."
It was good to see the Aussie seeming so relaxed after a torrid season during which she admitted she'd asked herself not so long ago: 'Should I be doing this anymore?" The next day, though, she was back out on the practice court and she now believes she's turned a corner.
The great unknown, though, of course, is what version of Williams will rock up after only just two recent doubles matches in nearly four years.
Asked what she expected, Joint concurred: "I'm expecting big serves and big forehands. She has an amazing serve-plus-one, and she's a great returner.
"So I'm expecting shorter rallies, just from how hard she hits the ball. I'll have to be really ready for the first couple games, try and get a good start to maybe catch her off guard a little bit."
