Metz have been relegated from Ligue 1 after slumping to a 4-0 defeat to Lorient, who move closer to safety as a result.
First-half strikes from Mehdi Mostefa and Romain Philippoteaux gave the visitors a comfortable advantage before Lamine Kone and Jordan Ayew goals sealed Lorient three points and condemned Les Granats to playing in France's second tier next season.
Metz almost took the lead inside three minutes when ex-Chelsea winger Florent Malouda forced an early save out of Benjamin Lecomte.
However, it was Les Merlus who found the breakthrough when Mostefa tucked home from a corner, moments after Ayew went close to scoring.
Fakhreddine Ben Youssef offered Metz their best chance of a first-half equaliser on 20 minutes, but his effort was straight at Lecomte.
Instead, Lorient extended their lead late in the opening period when Philippoteaux latched onto Didier Ndong's pass before finding the bottom corner of Anthony Mfa Mezui's net.
Metz's drop to Ligue 2 was confirmed early in the second period when Kone added a third for Les Merlus.
Lorient, who are now four points above the drop zone with two games left to play, added a fourth with six minutes remaining as Ayew got in on the act.