This study aimed to adapt and validate the Transactive Memory System Scale in Sport with professional players. The participants were 375 male and 229 female professional players, aged between 15 and 38 years ( M = 24.34, SD = 4.03). The structure of the instrument was analyzed through confirmatory procedures and supporting the hypothesized theoretical model of one second-order factor and three first-order factors. Results showed that the hierarchical structure solution had a good fit of the data. Thus, the structure of the Transactive Memory System Scale in Sport is composed with one second-order factor and three first-order factors: specialization, credibility, and coordination. Furthermore, reliability and invariance across gender were also shown, and the scale had good concurrent validity. These results suggest that the Transactive Memory System Scale in Sport is a valid and reliable instrument to measure the transactive memory system in sport with male and female professional players.