Nice, who dropped points against bottom side Metz last weekend, were again held by a struggling side as second-bottom Bastia - reduced to 10 men - pegged back Mario Balotelli’s side 1-1 on Friday.
Monaco, however, made no mistake against bottom-of-the-table Lorient.
Leonardo Jardim’s men were 4-0 up in under hour as Brazilian Boschilia scored on 24 and 28 minutes with Valere Germain adding further goals on 37 and 59 minutes.
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The victory means Monaco move two pints clear of Nice and three clear of Paris St Germain who beat Nantes 2-0 to remain just three points adrift of pole position.
Monaco’s latest four-goal haul – the ninth time they’ve scored that tally or more this season – leaves the Principality side with an average better than three goals per game this season – still comfortably the best in Europe.
Next Sunday evening the Red and Whites travel to Paris to take on Paris St Germain but their far superior goal difference means that even if they lose, PSG will not overtake them.
PSG have been imperious at home this season, where they remain unbeaten and have conceded just three goals to date.
