The purpose of the present study was to examine the effectiveness of imagery on muscular endurance, dynamic balance, and functional stability in athletes who sustained a grade II ankle sprain. The sample consisted of 20 active athletes (aged from 18 to 30 years) with a grade II ankle sprain, as confirmed by ultrasound testing. The participants were randomly divided into two groups of 10 participants each; one experimental and one control group. The experimental group received 12 individual sessions of imagery rehearsal in addition to a normal course of physical therapy, while the control group followed only the physical therapy treatment. Results revealed significant differences only in the variable of muscular endurance. This study partly supports the contribution of imagery to the functional rehabilitation of grade II ankle sprain. Further research should be conducted to examine the effect of imagery on the functional rehabilitation of sport injuries using other tests of functional rehabilitation along with larger sample sizes.