Jimmy Briand scored the winner in a 2-1 victory for Guingamp as Gazelec Ajaccio were condemned to another week at the bottom of Ligue 1.
Chances were difficult to come by for much of the early stages, and it was the hosts who made the first breakthrough midway through the first half when the influential Briand released Sloan Privat, who displayed great composure to slot home.
Guingamp were unable to reach the break with a lead as Ajaccio pegged them back 10 minutes before the interval when Kader Mangane converted from David Ducourtioux's inviting cross.
However, they were dealt a huge blow just a few moments later when Issiaga Sylla picked up a second yellow card to leave his side with a huge second-half challenge.
Predictably, Guingamp appeared rejuvenated after the interval and they started to step up the tempo to pile the pressure on the visiting defence.
A reward arrived as Briand made another vital contribution as Lars Jacobsen's cross was eventually drilled home by the former Hannover forward.
It was a comfortable finish for Guingamp, who dominated possession as Ajaccio sruggled to produce a response to falling behind for the second time in the night.