Thanasi Kokkinakis set Lleyton Hewitt's team on their way with a tight boilover win against Arthur Fils but Alexei Popyrin came up against an inspired Ugo Humbert.
That meant the match, the first of the group stage round-robin in Valencia, Spain, came down to the doubles.
Max Purcell and Matt Ebden delivered, beating Pierre-Hugues Herbert and Edouard Roger-Vasselin in three tense sets, 7-5 5-7 6-3.
With Spain and the Czech Republic to come it was a crucial result for an Australian team watched on the sidelines by Aussie No.1 Alex de Minaur, whose hip injury prevented him featuring.
Kokkinakis had got Australia off to the ideal start, defeating world No.24 Fils 7-6 (7-4) 7-6 (7-3).
The battling Kokkinakis came back from 4-2 down in the second set, saving a series of break points to force the tiebreak.
A brilliant running backhand return was a key shot.
"If I don't make that, I don't think I'm coming back from a double breakdown in the second set," said 86th-ranked Kokkinakis.
That — Davis Cup (@DavisCup) @TKokkinakis backhand on the run �#DavisCup | @TennisAustralia pic.twitter.com/IS1USkVEzCSeptember 10, 2024
Kokkinakis said he stepped up his preparation when he saw, in New York, that de Minaur was still to fully recover from the hip injury he suffered at Wimbledon, realising he might start.
"After I saw Alex at the US Open I knew he wasn't 100 per cent and was struggling, so my focus changed. I was like, 'I need to be ready here. I need to have a little bit more purpose when I train'.
"Lleyton trusted me to go in there and do the job and give my best effort and I'm very happy with the way it went."
With Popyrin, the conqueror of Novak Djokovic next up, Australia seemed poised for a winning 2-0 lead. But Popyrin ran into Humbert in inspired form.
The French world No.17 blew Popyrin away 6-3 6-2, the second set taking less than half-an-hour.Â
Humbert won 80 per cent of his first serve points, Popyrin less than 60. Humbert forced 23 errors from his opponent and hit 16 winners, Popyrin hit five.
Alexei Popyrin's good form deserted him in Valencia, the Australian losing to Ugo Humbert. (EPA PHOTO)
That meant the doubles became the decisive rubber, with Purcell, doubles champion with Jordan Thompson at Flushing Meadows, reprising his Wimbledon 2022 winning partnership with doubles veteran Ebden.
The match began badly for France with Herbert not only double-faulting his first-serve point but doing so by whacking the serve into his teammate. However, France managed to save a break point and hold, and the set went with serve to 6-5.
Then Ebden unveiled three successive passes to break Roger-Vasselin and take the first set.
The second followed a similar pattern with a brilliant Purcell lob earning a match-point break point at 5-4. Â
But this time Herbert held, following it up by breaking Ebden.
Australia roared back, breaking immediately in the third to seize a 3-0 lead. Four holds later Purcell was serving for the match. He went 0-30 down but drew level, only to double-fault.
The Aussies saved the break point and, after on the third match point, Purcell settled it with an ace.
"I knew if I could land a few good serves it was all over, and luckily I did," said Purcell.
Hewitt, who was in the last Australian team to win the Davis Cup in 2003, said on court, "when you have these boys going out for a live doubles it gives you a lot of confidence, they have done it the last couple of years for us and they did it again."
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