Large Granular Lymphocytic (LGL) leukemia is a rare lymphoproliferative disorder with a peculiar association with Rheumatoid Arthritis (RA). The most common feature is neutropenia and patients can have splenomegaly, resembling Felty’s Syndrome. These diseases have similar clinical and laboratory abnormalities, but the diagnosis of T-cell LGL (T-LGL) leukemia requires evidence of clonality. Even though T-LGL leukemia is indolent in most cases, inadequate treatment when it is indicated can lead to significant morbidity and mortality, mainly associated with recurrent infections. We present two clinical cases that emphasize the emerging role of Rituximab as an effective therapeutic option in patients with T-LGL and RA.