The inherent low to moderate level of filtering in a receiver makes their developement challenging in terms of linearity. In this article, the impact of the blockers on the RF section performance, combinaison of an antenna filter and an LNA, is investigated. The Gain Drop (GD) and noise factor increase (Finc) are described as a function of the LNA linearity (ICP1, IIPx) and the filter rejection (L1). The measurement results of two LNA notably highlight the large contribution of IM3 on the NF in a multi-blocker scenario.