Joint's nervy three-set win has taken her to another quarter-final on a day when six of her compatriots were reaching the final round of Wimbledon qualifying, with the tantalising prospect of 19 Aussies featuring in Friday's draw for the grass-court grand slam should they all win on Thursday.
The 19-year-old meteoric riser Joint is already in the main draw but could be joined by an even younger teen, world No.209 Emerson Jones, who must beat talented French world No.90 Diane Parry in the final round of qualifying to become the youngest Aussie to make the women's main draw since Ash Barty in 2012.
At the English seaside resort of Eastbourne, US-born Queenslander Joint, still an absolute beginner on grass courts, showed she's adapting to the surface as quickly as she did to clay, having earned her first tournament win on the red stuff just before the French Open.
Having lost the first set to the rejuvenated former US Open champ Raducanu, Joint, even when struggling to keep her footing on the lush Devonshire Park court, looked completely at home with her crisp hitting, particularly on the backhand flank, as she recovered to win 4-6 6-1 7-6 (7-4).
Joint dominated from the moment she lost the opener, winning 11 of the next 14 games to move into a 5-2 lead in the decider, only to start to get nervous as the winning line approached.
Raducanu battled back, three times breaking Joint as she served for the match, but the youngster kept her nerve better in the tiebreak, even when 4-3 down, as she scented just second ever tour-level grass-court win after her victory over grand slam finalist Ons Jabeur on Monday.
Joint delivered a fantastic off-balance backhand to earn match point at 6-4 and then delivered her third ace of the match for one of the best wins in a burgeoning career that's seen her jump from 1384 in the world 18 months ago to her current ranking of 51.
The Australian No.2 will definitely move inside the top-50 if she can beat Russian world No.69 Anna Blinkova in the quarter-finals.
"Today was really tough, there was a lot of up and downs, lot of momentum switches, but I'm really glad that I was able to tough it out in the end," said Joint, who'd lost to Raducanu on clay at the Italian Open.
"I'm really glad I was able to win this one. I definitely try to hit the lines. Doesn't always work, so I'm glad it worked today. But I think I'm an aggressive player, I like to use my backhand and am trying to learn how to play all-court."
Meanwhile, at Roehampton, a 10-minute drive away from Wimbledon, 16-year-old Jones, Talia Gibson, Priscilla Hon, Alex Bolt, Li Tu and James McCabe all booked places in the last round of qualifying.
Gold Coast star Jones is on the verge of her first grand slam main draw outside Australia after beating Serbian Lola Radivojevic 6-4 6-4 while the Australian win of the day came from Adelaide's Li who saved four match points en route to outlasting Japan's Sho Shimabukuro 3-6 7-6 (10-8) 7-6 [11-9].
Bolt beat American Eliot Spizzirri 7-6 (7-5) 2-6 6-2, Philippines-born McCabe outplayed Argentine Roman Andres Burruchaga 6-1 6-4, Perth's Gibson battled past Dutchwoman Arianne Hartono 6-3 4-6 6-4 and Brisbane's Hon hammered Swiss Leonie Kung 6-1 6-3.
The biggest disappointment in the men's quallies was Ilkley Trophy winner Tristan Schoolkate bowing out in the third round to Lebanese Benjamin Hassan 7-6 (7-4) 6-3.
