A rare case of closed complete rupture of the flexor hallucis longus tendon at its groove in the posterior process of the talus is reported in a soccer player who developed pseudarthrosis of the posterolateral tubercle of the talus after a Shepherd's fracture. Partial rupture or tenosynovitis of the flexor hallucis longus tendon at this level is well known in classical ballet dancers and soccer players. Three cases of complete rupture of the flexor hallucis longus tendon near the metatarsophalangeal joint and three under the sustentaculum tali have been reported, but there have been no reports at the groove of the talus. Repair was accomplished by tendon graft, and active flexion of the interphalangeal joint is now possible.