This study examined content and intensity of anger prior to, during, and after best ever and worst ever performances in 43 high-level Spanish karate athletes using individualized anger profiling. Optimal and dysfunctional anger intensities were assessed using a modified version of Borg’s Category Ratio (CR-10) scale. Anger profiling was supplemented with positive and negative emotion profiling. As expected, content of anger descriptors was highly idiosyncratic. Moreover, great variability in optimal and dysfunctional anger intensities was found at individual and group levels. In best performances, anger was related to the generation of additional energy, whereas in worst performances, anger resulted from a perceived lack of resources or low readiness to perform. Athletes generated different anger descriptors in performance and in non-sport performance situations (overlap ranged from 0 to .35). The results support the use of an idiographic approach in the study of anger states.