Grandiose narcissism may be debilitative to athlete training because the opportunity for self-enhancement that motivates narcissists to strive is normally absent in training environments. However, this view ignores the divergent influences of the self-inflated (reflecting over-confidence) and dominant (reflecting willingness for dominance) facets of grandiose narcissism. We expected that self-inflated narcissism would undermine athlete training, but only when dominant narcissism was low. This is because dominant narcissism may serve as the catalyst that drives those with self-inflated narcissism to train well. We further considered goal-setting as a practical means of alleviating the negative influence of self-inflated narcissism in training. Goal-setting provides athletes with an exciting vision of the future and thus can be an important self-enhancement strategy to engage narcissistic athletes in training. In the present study, 321 athletes completed the Narcissistic Personality Inventory (NPI-40) and the goal-setting subscale in the Test of Performance Strategies-3 (TOPS-3). Coaches of these athletes assessed training behaviors using the Quality of Training Inventory (QTI). Self-inflated narcissism predicted higher levels of (coach-rated) distractibility and poorer quality of preparation only when both dominant narcissism and goal-setting were low (and not when either was high). The findings suggest that dominant narcissism and goal-setting protect against the adverse influences of self-inflated narcissism on athlete training. The work underscores the importance of considering grandiose narcissism as a multidimensional construct and supports goal-setting as a useful self-enhancement strategy.