A haymaking machine comprises a harvesting device comprising a rotor driven about an axis which is horizontal and perpendicular to a direction of advance during work, teeth, the points of which describe a curve envelope when the rotor turns about the axis, and a conveyor moving the plants transversely to the direction of advance, the machine comprising a deflector connected to an arm connected to the harvesting device by means of an articulation, about which the arm can pivot between a first position in which the deflector is arranged, during work, beside and at a distance from a lateral end of the harvesting device, and a second position. In the second position and considering the machine during work, the deflector and the arm extend flat and at least partially above the harvesting device.