Concussions are a brain injury that affects the athlete on and off the playing field. The aim of our investigation was to give PE teachers another strategy to use in addition to the recommended approaches set forth by national organizations to convey the message to adolescents regarding the negative effects of concussion. Using the website www.mlssoccer.com, we evaluated the performance measures of MLS players. We compared career performance measures of a control group to the career performance measures of a concussed group, compared career performance measures per position, and compared career performance measures occurring prior to concussion onset to performance measures obtained after concussion occurrence for the concussed group. Of the 2,214 listed players, 288 were eligible for the study. From our sample, 34% sustained a concussion while competing in MLS and 66% were placed in the control group (nonconcussed). In a comparison of the control to the concussed group, total number of shots decreased per season for the concussed group. When the performance measures of both groups were compared by position, midfielders had fewer shots per season, and total shots on goal per season had a trend toward statistical significance. In the comparison of games measures before and after concussion, the total number of seasons and the average games played, total minutes, and shots on goal all decreased per season after concussion occurrence. Concussions negatively affected performance measures of MLS players. PE teachers can use this data to engage with their students about the importance of preventing concussions.