Monaco’s grip on a Champions League qualifying berth in Ligue 1 loosened further on Sunday as the principality side were swept away by Lille, losing 4-1 in far northern France.
Morgan Amalfitano had Lille in front at the break before a dramatic second half saw both sides reduced to 10 men, Renato Civelli’s red card for the hosts being followed by Elderson Echiejile’s dismissal for Monaco.
Eder, Mounir Obbadi and Djibril Sidibe added further goals for Lille before Fares Bahlouli netted a consolation for a well beaten Monaco side.
Last month’s 2-0 victory at champions Paris Saint-Germain is Monaco’s only win in their last six games and this weekend has seen them surrender second place in the table to Lyon.
Even third spot, which brings with it a place in the Champions League third qualifying round, is far from secure with Rennes, Saint-Etienne, Nice and even Lille still in contention.
Lille have been transformed from relegation contenders into European hopefuls under Frederic Antonetti and they are seventh after claiming a fifth consecutive win.
Amalfitano had hit the post before he controlled an Eder knockdown and fired into the roof of the net on 37 minutes at the Stade Pierre-Mauroy.
Lille had Civelli sent off shortly after the restart after the Argentine shoved Ricardo Carvalho to the floor off the ball, but Echiejile followed on 63 minutes for a reckless challenge on Sebastien Corchia.
The hosts doubled their lead soon after that, with Portugal forward Eder stroking a shot low into the bottom-left corner to mark an impressive display with a goal.
Sofiane Boufal then set up Obbadi for the third goal and Junior Tallo picked out Sidibe to make it four with a finish through the legs of Monaco goalkeeper Danijel Subasic.
Substitute Bahlouli netted at the death for Leonardo Jardim’s side, who will now be keeping a close eye on the outcome of the meeting of Nice and Rennes later on Sunday.
Lyon won 2-0 at Montpellier on Friday thanks to a Maxwell Cornet brace while Saint-Etienne were 1-0 winners against already-relegated Troyes.
Champions Paris Saint-Germain warmed up for their Champions League showdown with Manchester City by winning 2-0 at Guingamp on Saturday with a shadow line-up.
Lucas Moura scored both goals for the capital side in Brittany, with the first coming from the penalty spot.