Background <p>This case report explores the rare complication of a pseudocyclops lesion within an anterior cruciate ligament autograft, identified in a patient with a recent knee injury and an existing anterior cruciate ligament autograft graft. Notably, this case was managed conservatively, diverging from typical surgical interventions, and resulted in a successful outcome.</p> Case presentation <p>A 37-year-old Caucasian male with a prior anterior cruciate ligament autograft sustained a new knee injury; 9 days post-injury, he presented with persistent pain and swelling, exacerbated by weight-bearing, and limited knee extension, though no instability was noted. Non-contrast magnetic resonance imaging revealed a partial tear in the distal anterior fibers of the anterior cruciate ligament autograft, with a 2.5 × 1.3&#xa0;cm extrusion extending toward Hoffa’s fat pad. The patient was prescribed nonsurgical rehabilitation, which proved effective.</p> Conclusions <p>This case underscores the potential of conservative management for pseudocyclops lesions. The successful non-surgical treatment of the pseudocyclops lesion expands the therapeutic options available for similar cases and contributes to the broader understanding of postoperative anterior cruciate ligament autograft pathologies.</p>