Wales Under-20s slipped to a 47-15 defeat to a powerful France under 20s side in Colwyn Bay – in a game that featured five young Dragons.
Prop Adam Williams and lock Ryan Woodman started in the pack and scrum half Morgan Lloyd played at nine. Hooker Connor Chapman and back row Ben Moa both featured from the bench.
Romain Fonnicola and Connor Sa put France in control but a penalty try and a Beni Williams score saw Wales fight back to within two points.
But Sa's second and further tries from Enzo Reybier, Simon Tarel and Max Auriac saw France seal a crucial bonus point win ahead of their final game against Ireland.
Byron Hayward's Welsh youngsters are fourth in the Championship with Italy their final opponents a week on Sunday.
Wales U20s: Iestyn Hopkins; Harri Houston, Bryn Bradley, Joe Hawkins (capt), Tom Florence; Jac Lloyd, Morgan Lloyd; Joe Cowell, Morgan Veness, Adam Williams, Benji Williams, Ryan Woodman, Ben Gregory, Ethan Fackrell, Morgan Morse.
Replacements: Connor Chapman, Cameron Jones, Nathan Evans, Lewis Jones, Ben Moa, Harri Williams, Cameron Winnett, Eddie James.
France U20s: Leo Barre; Romain Fonnicola, Emilien Gailleton (capt), Louis Le Brun, Enzo Reybier; Emile Dayral, Baptiste Jauneau; Thomas Moukoro, Connor Sa, Thomas Cretu, Samuel M'Foudi,Hugo Auradou, Leo Banos, Noe Della Schiava, Theo Ntamack
Replacements: Victor Montgaillard, Matis Perchaud, Elliot Yemsi, Ugo Vignolles, Killian Tixeront, Clement Garrigues, Simon Tarel, Max Auriac