The main purpose of this study was to examine interaction effects between skill level and performance contexts on the experience of flow in adolescent tennis players. The study employed a factorial design to examine differences in flow frequency between competition and training settings and the independent groups factor of ranking list and club players. Junior tennis players (55 males, 29 females) completed the Dispositional Flow Scale-2 in training and competition settings. A repeated-measure ANCOVA, with years of tennis experience and training hours per week as covariates, showed a significant main effect for skill level, F(1,82)=6.67, p<0.05, n2p=0.08, a significant main effect for performance contexts, F(1,82)=7.69, p<0.01, n2p=0.09, and a significant disordinal interaction, F(1,82)=9.93, p<0.01, n2p=0.11. Lower skilled athletes experienced flow with similar frequency across performance contexts, whereas advanced players experienced flow more often during training than competition. Qualitative results showed that club players’ involvement in both performance contexts was mainly based on intrinsic reasons, whereas ranking list players reported intrinsic reasons for training, but a high number of extrinsic reasons for competition. Future studies should take propositions of the flow model into account in order to advance theoretical developments on interaction effects and shed more light into the complex processes underlying flow in sport.