Causes of groin pain (sports)

Hernia
FAI
Labral tear
iliopsoas tendinitis
iliotibial band syndrome
rectus abdominis strain
adductor muscle-tendon dysfunction
rectus abdominis - adductor longus aponeurosis tear
stress fracture
apophysisits

Reference:
Omar I M et al. Athletic Pubalgia and "Sports Hernia": Optimal MR Imaging Technique and Findings. RadioGraphics 2008;28:1415-1438