Tony Gold described the defeat against Arlesey Town as a kick in the teeth.
London Lions left the Armadillo Stadium empty-handed after going down in a five-goal thriller.
Gold identified a "new-found resilience" in defence as the platform for Max Kyte to register his 11th goal of the season on the stroke of half-time.
Town scored twice early in the second half, but Josh Kennet hauled Lions level following a moment of individual brilliance before Town won it late on.
Gold said: "The new level of performance from certain individuals was most pleasing."