Late call-up Madison Keys put defending champions the United States through to a Fed Cup final against the Czech Republic on Sunday.
Keys was drafted in to replace CoCo Vandeweghe for the fourth rubber against France's Pauline Parmentier after Sloane Stephens thrashed Kristina Mladenovic to put the holders 2-1 up.
And the 23-year-old justified the faith shown in her by US team captain Kathy Rinaldi, defeating Parmentier 7-6 (7-4) 6-4 in Aix-en-Provence to knock the hosts out.
Petra Kvitova got the job done for 10-time champions the Czech Republic in the other semi-final against Germany, seeing off Angelique Kerber 6-2 6-2 to leave the majority of the crowd disappointed in Stuttgart.
Both teams will now prepare for the final, which takes place on the weekend of November 10-11.
IT'S GOING TO BE CRAZY
Keys' selection at the expense of Vandeweghe caused a bit of a stir, but she made sure to leave her mark by defeating France's Parmentier.
It was not all smooth sailing, Parmentier racing ahead in the second set, only to fall short as Keys claimed it 6-4.
"It feels amazing, but not for me - to do that for this team and help us back to the final," Keys told the competition's official website.
"I knew [Pauline] would play well, she was so good against Sloane yesterday.
"I love playing in atmospheres like this, even if they are not all cheering for you it still makes for a great game.
"It is going to be a crazy final!"
SLOANE STARS FOR THE STATES
There was no such danger of Stephens conceding her lead in the earlier rubber, as she made light work of Mladenovic.
It took Stephens just 54 minutes to overcome her opponent 6-2 6-0, and set the stage for Keys' wonderful performance.
CZECHS IN CRUISE CONTROL
It could well have been a hostile atmosphere for the Czech Republic's Kvitova, but the world number 10 held her nerve to ease past Kerber in convincing fashion.
Kvitova and Karolina Pliskova had put the Czechs well in control on day one, and although Julia Georges made it 2-1, Kerber could not complete the comeback for Germany.
In fact, Kerber's hopes were swiftly dashed - Kvitova picking up where she left off on Saturday to send the Czechs through.
PLAY-OFF DELIGHT FOR BELGIUM AND BELARUS
In the World Group play-offs, there were wins for Belarus, Romania, Australia and Belgium.
|Reported Liverpool target Dabbur to undergo Sevilla medical|
|Lebanon v North Korea: Radulovic calls on players to make history|
|MLS MVP Martinez signs five-year contract with Atlanta|
|WBC set deadline for Wilder-Fury rematch|
|Iran 0 Iraq 0: Team Melli top Group D after dull draw|
|Vietnam 2 Yemen 0: Quang Hai shines to give Golden Dragons hope|
|Bielsa admits to spying on all Leeds´ opponents|
|Valverde open to arrivals amid De Jong tug-of-war|
|Sexton named in Ireland squad for Six Nations openers|
|Higuain benched for Supercoppa Italiana amid Chelsea links|
|De Grandhomme, Latham and Santner back in Black Caps squad|
|Oman v Turkmenistan: Verbeek tells players to ´score as many as possible´|
|Japan v Uzbekistan: Cuper not distracted by potential last-16 opponents|
|Brown desperate for England recall|
|Lowry ties course record in Abu Dhabi|
|James is playing for Bayern future – Kovac|
|Wizards can compete for playoffs in LeBron-less East despite injuries - Brooks|
|Kyrgyzstan 3 Philippines 1: Lux hat-trick gives White Falcons third-place hope|
|South Korea 2 China 0: Son sets the standard as Bento´s men take top spot|
|Saudi Arabia v Qatar: Top spot on the line in Group E|
|Wasps pull off Fekitoa coup|
|Fresh injury woe for Real Madrid defender Vallejo|
|Home sweet home for Wozniacki as Stephens conquers Melbourne demons|
|Nadal: Victory over Ebden a step forward|
|Proteas rest Steyn and De Kock for opening ODIs|
|Nadal and Federer march on as rising stars prosper|
|Barcelona president Bartomeu convinced Valverde will stay|
|Inter forward Keita suffers thigh injury|
|Nadal races into third round with easy Ebden win|
|Kimmich ´perfect´ for Barcelona, says Xavi|
|Richardson and Nabi inspire Renegades´ rout of Sixers|
|This Liverpool isn´t a team of chokers – Mane|
|Central Coast Mariners 2 Melbourne City 1: Late Simon winner ends 10-match losing streak|
|Bryan backs Murray to return after hip resurfacing surgery|
|Scotland coach Townsend turns to trio of uncapped hookers|
|Spurs´ Aurier arrested on suspicion of assault, released without charge|
|That was a fireworks show - Warriors revel in record-breaking first quarter|
|We are in talks with Chelsea – Salihamidzic reiterates interest in Hudson-Odoi|
|´Proud´ Messi recognises impact of team-mates after reaching 400 LaLiga goals|
|Henry v Vieira: The Arsene Wenger proteges to move into coaching|
|Federer enjoys ´cat and mouse´ win over Evans|
|Wozniacki cruises through in Melbourne|
|Federer maintains perfect Australian Open second-round record|
|Warriors set NBA record, Butler´s 76ers rout Timberwolves|
|´I like the fact we beat them´ - 76ers´ Butler revels in win over Timberwolves|
|Murray says he´ll ´probably´ have operation|
|Australian Open tribute for Andy Murray surprises brother Jamie|
|Warriors score NBA record 51 points in first quarter against Nuggets|
|Panthers owner Tepper doesn´t rule out Newton missing 2019 because of shoulder injury|
|De Ligt will be world´s best centre-back – Koeman|
|Ronaldo a ´perfect machine´, says Gattuso|
|Barcelona? I can´t say anything - Stuani|
|Silva upbeat about Man City title chances|
|Celtics youngsters say Irving´s callout ´came from a good place´|
|NFL playoffs: Patrick Mahomes v Tom Brady|
|NFL playoffs: Jared Goff v Drew Brees|
|Sixers sign Brewer to 10-day contract|
|Lozano and Morgan scoop CONCACAF awards|
|Lakers ´optimistic´ about LeBron injury|
|Giants produce mammoth fourth quarter against Nymburk|
|Austin FC to join MLS in 2021|
|Henry, Vieira look forward to reunion when Monaco host Nice|
|Barcelona reject Neymar phone call reports|
|Wentz is the quarterback ´going forward´, says Eagles coach Pederson|
|Gattuso: Higuain has not asked to leave|
|Drew Brees by the Opta numbers: 10 facts for QB´s milestone birthday|
|Harry Kane injury: England captain´s history of ankle woe|
|Harry Kane injury: Opta numbers suggest Spurs struggles|
|Harry Kane injury: Tottenham´s options in striker´s absence|
|Allegri: Supercoppa clash practice for Champions League knockouts|