Georgia's Gela Aprasidze kicked two late long-range penalties to take Montpellier to next weekend's Top 14 final with a 19-10 win over Bordeaux-Begles on Saturday.
Substitute scrum-half Aprasdize's contribution came in the final 11 minutes and his club will meet Castres, who beat champions Toulouse 24 hours earlier, next Friday at the Stade de France in a re-run of their 2018 meeting.
"The essential was to win, in a pretty way or not, we don't care," Montpellier full-back Anthon Bouthier told reporters.
"With Gela, we knew he had it in his legs. The day before he kicked some from 60 metres.
"He came on, he was fresh, knock-out rugby is about knowing taking the points when on offer," he added.
Montpellier head coach Philippe Saint-Andre handed France three-quarter Arthur Vincent his first start since October after he recovered from a serious knee injury.
Argentina forward Guido Petti returned to Bordeaux-Begles' side following a knee injury sustained against Perpignan on June 5.
The game started at a gallop as the sides were level 10-10 by the 30 degrees celsius-enforced water break after 20 minutes.
Maxime Lucu kicked a penalty for Bordeaux-Begles before Vincent Rattez crossed in the corner for Montpellier from a Paolo Garbisi assist before the Italy fly-half slotted a clinical drop goal.
Lucu brought the sides level as half-back partner Matthieu Jalibert crossed after a 30 metre break.
- 'No tension' -
Saint-Andre's outfit led at the break as Bouthier repeated Garbisi's efforts with a drop goal just before the break.
Aprasidze, 24, broke the deadlock of a tense second half with an 69th minute penalty from more than 50 metres to make it 16-10.
Despite their efforts Aprasidze, who came on for Benoit Paillague for the closing quarter of an hour, slotted a 78th minute penalty from five metres closer than his earlier effort to clinch his side's place in next week's showpiece event in Paris.
With defeat, Bordeaux-Begles former France internationals Louis Picamoles and Francois Trinh-Duc played the last games of their careers.
Christophe Urios' side lost a second domestic semi-final in the space of 12 months and last week Jalibert said his team-mates played for themselves and not the outspoken head coach, who had criticised them seven days earlier.
"There was never tension," Jalibert told reporters.
"Things were said in the press. We never gave up on Christophe, he never gave up on us," he added.
Despite reaching next weekend's final the France players involved will be omitted from next month's tour of Japan with the first Test in Toyota on July 2.
Aprasidze's Georgia face an Argentina invitational side as well as Italy and Portugal in matches next month.