Bottom of the table on 25 points heading into the penultimate matchday, Clermont needed to better the result of 16th-placed Metz, who sat four points better off in the relegation playoff place ahead of their trip to Strasbourg.
However, Metz's exploits against Patrick Vieira's side were rendered inconsequential, as Les Lanciers were undone by a 53rd-minute Orel Mangala goal to confirm their demotion back down to Ligue 2.
Pascal Gastien's 18th-placed side are now four points adrift of safety with only three left to fight for, meaning that they will be playing second-tier football in 2024-25 after three mixed seasons in the top flight.
Upon their promotion from Ligue 2 in 2020-21, Clermont finished 17th in the 20-team Ligue 1 table in 2021-22 before achieving a surprise eighth-placed ranking last term, but their fortunes suffered a dramatic nosedive this time around.
Lorient - who entered the weekend just one place and one point better off than Clermont - could have also been condemned to the drop tonight, but Les Merlus are still mathematically safe thanks to a dramatic turn of events in Strasbourg.
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Metz, sitting in the relegation playoff place, entered the weekend on 29 points compared to 26 for Lorient, who therefore needed to at least match Les Grenats' result to take the fight for survival down to the final day.
Regis Le Bris's men faced a daunting test away to Marseille, though, and they came out on the wrong end of a 3-1 defeat, as Pierre-Emerick Aubameyang's brace and a Samuel Gigot effort cancelled out Benjamin Mendy's response.
Lorient appeared to be joining Clermont in the second tier, as Metz talisman Georges Mikautadze put his side 1-0 up against Strasbourg, a narrow lead that they clung onto heading into the dying embers of the contest.
However, there would be two late twists to the tale, as Emmanuel Emegha equalised for Vieira's men in the 89th minute, before Chelsea loanee Andrey Santos completed a remarkable turnaround in injury time.
As a result, Lorient remain three points behind Metz and could still pip Les Grenats to the relegation playoff place on the final day, although they possess a far inferior goal difference of -26 compared to -20 for Metz.
Elsewhere on Sunday night, Kylian Mbappe's final home game for Paris Saint-Germain did not go to plan as Toulouse beat the champions 3-1 at the Parc des Princes, while Monaco overcame Montpellier HSC 2-0 to guarantee a second-placed finish and return to the Champions League.
Lille and Brest have also secured top-four placements, while Nantes are mathematically safe despite going down 2-1 to the former at home.