Aloys Nong scored two late goals to hand Mons a come-from-behind 3-1 win over Standard Liege in the Belgian First Division on Sunday.
Ibrahima Cisse opened the scoring for Liege in the 13th minute, but the home side were back on level terms when Mustapha Jarju found the net on 34 minutes.
The contest appeared headed for a stalemate until Nong put Mons in front with an 88th-minute goal against his former side.
The Cameroonian doubled the advantage in stoppage time, lifting Mons to eighth on the table with 15 points.
For Ron Jans' Liege, it was their fifth loss in their past six league matches, leaving them 12th on 13 points.