This report describes a case of large colon volvulus in a 6-year-old Thoroughbred mare used for tent pegging sport by the Police department. The mare was presented in severe and acute pain from the last 5-6 hours (while returning after national games) with injected mucous membrane and capillary refill time >3secs. The mare was immediately anaesthetized and subjected to surgery. Sub-serosal hemorrhages and edema was evident on the mesentery of left ventral and dorsal colons. The condition was diagnosed as volvulus (>360⁰) of the left ventral colon. The volvulus was corrected and pelvic flexure was emptied and flushed. The mare recovered from anesthesia but experienced moderate pain for the next 5-6 hours. Uneventful recovery was reported on the next day with no pain, passed feces and took some green fodder. The mare recovered and resumed athletic performance in the subsequent7-8 months. The report recommends early referral for surgery in large colon volvulus for favourable prognosis and also highlights the pre- and post-surgery serial monitoring of clinical, haematological and biochemical parameters.