Veteran Pauline Parmentier defeated a hobbling Irina-Camelia Begu 6-3, 2-6, 6-2 to pull France level at 2-2 in their Fed Cup semi-final with Romania on Sunday.
The result sent the tie in the northern city of Rouen into a deciding doubles after world number two Simona Halep had earlier battled back from a set down to defeat Caroline Garcia 6-7 (6/8), 6-3, 6-4, putting Romania within touching distance of a first Fed Cup final appearance since 1973.
The eventual winners will face Australia in November's final.
For late call-up Parmentier, victory represented a rare singles success.
The world number 53 had won just one of her last eight Fed Cup singles clashes, suffering back-to-back losses in the 2018 semi-final defeat against the United States.
Her victory push was aided, however, by a late ankle injury suffered by Begu, the world number 83 who had originally been scheduled to play only doubles.
Instead Halep was selected for the make-or-break doubles alongside Monica Niculescu with two-time champions France opting for Garcia and Kristina Mladenovic.
French Open champion Halep gave Romania a winning lead on Saturday by seeing off Mladenovic 6-3, 6-1 before Garcia swept past Mihaela Buzarnescu 6-3, 6-3 to level the tie.
"I knew it would be more difficult than yesterday," Halep told fedcup.com on Sunday after registering a ninth successive singles win in the tournament that Romania have yet to win.
"It felt like playing at home, that was how I was able to fight to the end. I won it for the fans who came here."
Halep's win over Garcia, her sixth in seven meetings, took almost three hours to complete with the crucial break in the final set coming in the eighth game when the French number one served up back-to-back double faults.
"It's never over until it's over," said Halep who required treatment on her left thigh midway through the second set.
Seven-time champions Australia made the championship match for the first time in 26 years by seeing off Belarus 3-2 in Brisbane when Ashleigh Barty and Samantha Stosur battled past Victoria Azarenka and Aryna Sabalenka 7-5, 3-6, 6-2.
The tie was sent into the crucial doubles match after two-time Australian Open champion Azarenka crushed Stosur 6-1, 6-1 in the reverse singles, following Barty sweeping past Sabalenka 6-2, 6-2.
"I could not have picked two more perfect athletes to compete. Ash and Sam are superstars," said captain Alicia Molik who will look to inspire a first title since 1974 for Australia in the final.
Barty called making the final "unbelievable" while Stosur said it was "super exciting".
"We knew it was going to be a tough one and we just so happy with how we played," added Stosur. "All the girls have worked so hard throughout the year and we really stick together."