Perez was injured during a collision at home plate during Saturday's WBC game, Kyle Glaser of Baseball America reports.
Although specifics of the injury aren't yet known, it would be a big blow for the Royals if their star catcher had to miss extended time. Perez had to be helped to the clubhouse by trainers after the incident, and it appeared to be an ankle injury. His status will be updated when more information is made available.