Purpose: Mucormycosis is a rare, aggressive, angioinvasive fungal infection that predominantly affects immunocompromised patients. Involvement of the hand is uncommon and may initially resemble routine bacterial infection, resulting in delayed diagnosis and progression despite standard management. This case report highlights the challenges of diagnosing and treating invasive hand mucormycosis in a high-risk patient. Case Report: A 55-year-old Indigenous Australian woman with poorly controlled type 2 diabetes mellitus, significant peripheral vascular disease, metastatic lung cancer and IVDU presented with a felon following minor penetrating trauma four days earlier. The infection extended to the flexor tendon sheath, midcarpal space and space of Parona. Despite extensive local disease, the patient remained systemically well. Serial clinical assessment, operative findings, and microbiological culture results were reviewed. Management: The patient underwent four sequential surgical debridements to achieve source control. Initial intraoperative cultures were polymicrobial, and broad-spectrum intravenous antibiotics were commenced. Fungal cultures from the initial debridement subsequently grew Mucor species, confirming invasive mucormycosis. Despite repeated aggressive debridement, there was persistent purulence, absence of granulation tissue, and progressive local disease. Given poor tissue viability, severe vasculopathy, and limited reconstructive potential, a multidisciplinary decision was made to proceed with staged transradial amputation to achieve definitive disease control. Conclusion: Invasive mucormycosis should be considered in immunocompromised patients presenting with hand infections unresponsive to standard surgical and antibiotic therapy. Early fungal identification, multidisciplinary decision-making, and timely escalation to radical surgical management may be critical to achieving disease control and preventing systemic spread.