Aim: To study the clinical course, investigatory findings, and the need for timely diagnosis of extranodal natural killer/T-cell lymphoma, nasal type (ENKTL-NT) and to understand the diagnostic difficulties and treatment options. Background: Extranodal natural killer/T-cell lymphoma, also known as “Stewart's Granuloma,” is a rare non-Hodgkin's lymphoma originating in the nasal cavity. It mostly arises from the malignant transformation of cytotoxic T cells. It is characterized by aggressive and rapidly progressing necrotic lesions involving the mid face, principally the nose and palate. It is a diagnosis made by the exclusion of other infective and granulomatous mid-facial lesions. Case description: A 35-year-old male presented with bilateral nasal obstruction for 20 days, left cheek swelling for 2 days, associated with progressive left-eye swelling and nasal regurgitation of fluids. Local examination showed extensive nasal crusting, and septal and palatal perforation. No clinical improvement was seen with empirical antibiotics and antifungals. Immunohistochemistry (IHC) was positive for cluster of differentiation (CD) 3 and 56, which led to a diagnosis of ENKTL-NT, and chemotherapy was started. However, he succumbed to coronavirus disease-2019 (COVID-19) disease during the course of treatment. Conclusion: Extranodal natural killer/T-cell lymphoma, nasal type is an aggressive form of non-Hodgkin's lymphoma with a clinical picture masquerading as acute invasive fungal sinusitis, mid-face granulomatous lesions, etc. This leads to delayed diagnosis, which in turn affects morbidity and mortality. Therefore, a timely and precise diagnosis with aggressive treatment is a must. Clinical significance: Extranodal natural killer/T-cell lymphoma, nasal type, is rare with rapid and aggressive local tissue necrosis and progression. Its refractory behavior to our initial treatment regimens raised suspicions. In the current challenging times, trying to decrease misdiagnosis is of paramount importance. Through this case report, we aim to alert fellow practitioners to keep this entity in the differential diagnosis of such an aggressive clinical picture with a short history.