Rennes coach Julien Stéphan and goalkeeper Romain Salin were full of praise for Adrian Truffert after the 18-year-old's match-winning debut sent the club top of the table.
On for the injured Faitout Maouassa before half-time, Truffert set up the equaliser for Steven Nzonzi with a pinpoint cross and then scored the winner with a left-footed shot in added time. Born in Belgium but an international with France at age-group level, Truffert was promoted to number two left-back for this season following the departures of Souleyman Doumbia and Jérémy Morel.
Following his remarkable debut we are liable to see much more of Truffert. Stéphan said: "We said we weren't going to sign a new left-back and that we were counting on him. He got his chance against Monaco, a first for him, and he showed his quality of crossing and shooting with a lot of personality.
"He is versatile and can cover the entire left flank but I like him starting further back. When you are capable of covering that much ground and you start further back, then you are capable of repeating those runs."
Salin, at 36 twice Truffert's age, backed up his boss: "He's a good little lad. He's a little bit introverted and very polite. You don't hear him speak very much but he's someone who is very positive. These youngsters are the soul of the group. La "Truffe" since the start of pre-season has shown he finds things easy and that he understands."
