Ghanaian forward Grejohn Kyei scored his second goal in the French Ligue 2 in their 4-2 loss against Valenciennes on Saturday.
RC Lens were hoping to end their two-match losing run when they travelled to the Stade du Hainaut to engage Valenciennes.
Philippe Montanier's men found their backs against the wall in the 14th minute after Tony Mauricio poked home from close range to hand the hosts a deserving lead but Kyei levelled the score line in the 36th minute, connecting to Yannick Gomis's low cut back pass.
Valenciennes regained their lead through Gaetan Robail in the 54th minute but again let the lead slip as Gomis pulled parity in the 63rd minute.
However, two goals from Sebastien Roudet and Mauricio in the 72nd and 87th minute respectively ensured Valenciennes finished the match with a 4-2 win.
Kyei picked a booking in the 28th minute before paving way for Souleymane Diarra in the 74th minute.