Genetic resistance to Tomato spotted wilt virus (TSWV) is important for yield protection in susceptible Arachis hypogaea (cultivated peanut). A single resistance source, PI 203396, has been used in breeding since the 1990’s. Recently, SSD6 and its resistant progeny NC94022, were introduced as a second source of resistance. A quantitative trait locus (QTL) was previously identified on chromosome A01. Within this QTL, a resistance gene and an insertion region from NC94022 were hypothesized to improve disease resistance. In the current study, the impact of this QTL and insertion region is explored through eight populations developed from both known sources of resistance. Presence of the insertion significantly improved field resistance with no agronomic trade-offs. Expression of candidate genes within this QTL and a nearby region with a large deletion are explored under mechanical TSWV inoculation. A glutamate receptor present only in NC94022 is selected as a candidate for further exploration.