Wigan's hopes of progressing to the knockout stages of the Europa League were dealt a major blow with a 2-1 home defeat by Zulte Waregem.
Junior Malanda's 88th-minute winner means qualification from Group D is now out of the Latics' hands.
After Rubin Kazan and Maribor had drawn earlier in the evening, Wigan knew victory at the DW Stadium would be enough to guarantee their passage through to the last 32.
But they will now need to beat Maribor in Slovenia in their final group game next month and hope Zulte lose to Rubin. The main sense of frustration for Owen Coyle and his squad will be that the damage was self-inflicted.
After Leon Barnett opened the scoring the hosts had no shortage of opportunities to extend their lead.
But they could not take any of them and in the 37th minute Zulte equalised when Lee Nicholls dropped Thorgan Hazard's shot into his own net.
Wigan were hit with a sucker punch in the 88th minute as Malanda found the top corner.