BackgroundReturn-to-play (RTP) criteria after a sport injury represent a key point in order to decrease the risk of subsequent re-injury.ObjectiveTo analyze how clinicians decide, in their daily practice, when a hamstring injured professional soccer player is fully able to get back to competitive activities.MethodsThirty-seven doctors for French and Belgian professional soccer clubs filled in a questionnaire formulated with multiple choice questions.ResultsNearly 80% of the questioned doctors declared to use at least 7 criteria in order to assess player's ability to return to competitive soccer after a hamstring injury. The most important ones are: complete pain relief, normalized muscle strength assessment, subjective feeling reported by the player, normalized flexibility and achievement of a specific soccer test. For some of these criteria, most notably muscle strength assessment, there is a lack of consensus about the choice of assessment parameters and the limit value allowing doctors to authorize or forbid RTP. Our study also highlighted the interest for clinicians to consider the opinion of physical therapists and physical trainers.ConclusionAfter a hamstring injury, clinicians for professional soccer clubs assess player's ability to return to full sport according to a “criteria-approach” instead of a “timed-based” approach. However, even if the scientific evidence about this topic is not sufficient at the moment, the implementation, in daily practice, of scientifically demonstrated assessment parameters and limit values should help the RTP decision and decrease the risk of re-injury.