A timepiece resonator mechanism including a structure and an inertia element oscillating about an axis, subjected to return forces exerted by a RCC flexure pivot with elastic resonator strips, which are each fixed to the structure and to the inertia element and essentially deformable in a plane perpendicular to the axis, straight and extending in parallel or coincident planes, the crossing, in projection onto a plane perpendicular to the axis, of their directions defining this axis, these strips are fixed on the inertia element side to a stiff element, comprised in an anti-shock element and on which are fixed the strips and which is integral with anti-shock flexible elements arranged to keep suspended the inertia element, the anti-shock element providing shock protection for the strips of the flexure pivot.