The 24-year-old from Guernsey had never played Grand Slam mixed doubles before teaming up with the Finn, but the pair added the American-Russian duo to their list of scalps after defeating defending champions Leander Paes and Martina Hingis in the third round.

The unseeded Kontinen and Watson had benefited from walkovers in their opening two rounds before making the most of their lucky breaks.

“We’ve played two matches together now and this is the most fun I think I’ve had on a doubles court,” a beaming Watson said after the pair’s 6-3, 6-2 quarter-final result. “Our games gel really well because we get on really well as a pairing.”

A nervous Watson double-faulted on her first match point, and then a second chance to seal it went awry when Kontinen netted a backhand volley.

The Finn made amends with a sharply angled backhand volley winner off Kudryatseva’s return before the Russian bunted a backhand volley long to seal the result after one hour and six minutes.

Kontinen gave a deadpan response as to what his tactic was when playing mixed doubles with his inexperienced partner. “I hope Heather picks up everything,” he quipped.

When asked who is boss on court, Kontinen and Watson simultaneously pointed at each other before the Brit laughed: “Actually, I was the boss a little bit there today.”

Watson and Kontinen will face another unseeded pair in the semi-finals after Austria’s Oliver Marach and Latvia’s Jelena Ostapenko finished in a canter to beat the Colombian duo of Juan-Sebastian Cabal and Mariana Duque-Marino.

Whichever partnership emerges triumphant in Saturday’s semi-final will take on No.15 seed Robert Farah and Anna-Lena Groenefeld for the title after the Colombian-German pair ground out a narrow 6-4, 2-6, 7-5 win over No.14 seeds Aisam Qureshi and Yaroslava Shvedova on Friday. Groenefeld has the chance to reclaim the mixed doubles crown she first landed seven years ago alongside Mark Knowles, while Farah will be bidding for his first taste of Grand Slam glory.

With Farah serving to stay in the match at 5-4 down in the third, Shvedova upped her aggression to help the pair close to within two points of the match. However, Farah conjured up three big first serves to help get out of trouble before levelling for 5-5.

They broke the Shvedova serve in the following game as Farah ripped a backhand past Qureshi for 6-5. They arrived at two match points when a Groenefeld serve down the T drew an easy putaway for Farah, and claimed it when Shvedova angled a forehand wide.