Mr. Smith was advised by his physician to lose weight and start jogging. He began to jog daily. On the sixth day, he was force to jump out of the way of a speeding car. He heard a snapping sound that was immediately followed by pain in his lower calf (gastrocnemius). A gap was visible between his swollen calf and his heel (calcaneous) and he was unable to plantar flex the foot. What do you think happened? *