The present invention relates to a pumping method in a pumping system (SP, SPP) comprising: a main lubricated rotary vane vacuum pump (3) with a gas inlet port (2) connected to a vacuum chamber (1) and a gas outlet port (4) leading into a conduit (5) before coming out into the gas outlet (8) of the pumping system (SP, SPP), a non-return valve (6) positioned in the conduit (5) between the gas outlet port (4) and the gas outlet (8), and an auxiliary lubricated rotary vane vacuum pump (7) connected in parallel to the non-return valve (6). According to this method, the main lubricated rotary vane vacuum pump (3) is activated in order to pump the gases contained in the vacuum chamber (1) through the gas outlet port (4), simultaneously the auxiliary lubricated rotary vane vacuum pump (7) is activated and continues to operate all the while that the main lubricated rotary vane vacuum pump (3) pumps the gases contained in the vacuum chamber (1) and/or all the while that the main lubricated rotary vane vacuum pump (3) maintains a defined pressure in the vacuum chamber (1). The present invention also relates to a pumping system (SP, SPP) able to be used to implement this method.