There was a subdued atmosphere in the under-renovation Stade Louis II, and the first-half action didn’t do too much to help that.
Some early pressure from Freiburg came to very little, and the first clear opportunity instead went the hosts' way as Mamadou Coulibaly watched a looped ball from Edan Diop drop in the area, where he tried to help it on, but Mio Backhaus made a decent stop.
Backhaus then kept out Paris Brunner at his near post, but he was powerless to stop the young striker as he gave his side the lead just moments before the half-time whistle.
Receiving it from Diop, Brunner deftly flicked the ball over Max Rosenfelder’s head and raced towards goal, slotting expertly inside the near post for his eighth of the season in all competitions.
Attempting to get back into it almost immediately as the second half began, Freiburg surged forward, and Monaco had some goal-line blocks to thank for stopping Lukas Kubler from scrambling in amid a flurry of corner kicks for the away side.
But Backhaus was called back into action to deny Brunner his second, and the visitors struggled to create anything from there.
Monaco eventually put the game beyond doubt when Flavio Nazinho pounced on a misplaced pass, feeding Ansu Fati, whose shot was parried by Backhaus for an arriving Lamine Camara to fire low into the net.
Even more shine was put on the result in stoppage time, with Fati getting one of his own by receiving Matthis Abline’s pass and turning brilliantly in the box to curl into the corner of the net.
It’s been a sensational start to life as Monaco manager for Filipe Luis, whose side have been almost flawless aside from their disappointing loss to Lorient at the weekend.
Julian Schuster is doing similarly well at Freiburg and will be confident that his side - who reached the UEFA Europa League final last season - will still progress to the knockout stages despite this result.