Lorient climbed clear of the Ligue 1 relegation zone with a remarkable 5-3 win at Marseille as the home side's alarming slump continued at the Stade Velodrome.
Three successive defeats had destroyed Marseille's hopes of landing the Ligue 1 title and they had not won at home since Jan. 31, but the odds were still stacked against visitors Lorient who knew nothing other than victory would take them out of the bottom three.
Florian Thauvin might have given Marseille a sixth-minute lead after combining with Andre-Pierre Gignac, but the Breton side were 2-0 ahead inside 13 minutes through Jordan Ayew and Francois Bellugou.
Ayew punished his former club with a fine volley after nine minutes following Lamine Gassama's cross and Romain Philippoteaux's clever back heel into his path.
Four minutes later Yann Jouffre's free-kick saw Ayew beat Jeremy Morel in the air and Bellugou's powerful header did the rest.
Dimitri Payet's pace offered Marseille hope of a comeback as the first half ended and Marcelo Bielsa's side were level halfway through the second period.
Ayew's brother Andre halved the deficit with a 59th-minute backheel flick after Payet's 35-metre free-kick had come back off a post and then Morel powered home a header eight minutes later from 12 yards.
But a minute later Philippoteaux put Lorient ahead again with a run through the static home defence, only for Belgian substitute Michy Batshuayi to equalise with 14 minutes remaining after racing onto a long ball from Alaixys Romao.
But Marseille capitulated in the final six minutes as Jordan Ayew scored his second from a fine solo run before Mathias Autret secured Lorient's first win in five games after home goalkeeper Steve Mandanda had parried his first effort.