Sonia’s best performance came at the 1987 Japan Cup, where she and Gina helped raise the level of the team in every technical skill. In general one could see that the whole team reached its peak in that tournament, and that all those countless days travelling and playing abroad, exercising regularly, and practicing 7 to 8 hours a day had finally paid off. Denisse Fajardo’s outside hitting was flawless, Gaby was a huge presence in the middle, and Denisse, Natalia, and Sonia brought incredible defence to the team. In fact, Sonia was named the tournament’s best passer, which seemed to eclipse her good hitting and blocking on the right side. Gina was given the tournament MVP Award, so the two most complete players on the team were duly rewarded. Two years later, at the World Cup in Japan, Sonia ended up setting in place of Rosa García, who hadn’t been given permission from her Italian club to join her teammates. She wasn’t even the team’s backup setter, but coach Man Bok Park had enough confidence in her all-around skills to assign her with such an important responsibility.

Sonia Heredia might not have surpassed her sister Aurora in matches as a starter on the team, but individually speaking, her all-around skills were much higher. Nevertheless, both could boast a second place finish: Sonia at the ’88 Olympics and Aurora at the ’82 World Championships. All in all, Sonia proved that being a complete player is an enormous asset for the overall success of a team.