Colombia maintained their perfect start in Group C with a 2-1 victory over Ivory Coast at the Estadio Nacional de Brasilia.
James Rodriguez and substitute Juan Quintero both scored in a six-minute period just past the hour mark, before Ivorian forward Gervinho pulled a goal back to set up a nervy finish with 17 minutes remaining.
Colombia, however, held firm to clinch all three points thanks to veteran defender Yepes, who earned his 100th cap for the national team.
"He was playing against the elite of Europe, Gervinho, Wilfried Bony, Salomon Kalou, all physically strong with great technique," said Pekerman of the 38-year-old.
"Yepes has a great mentality. He has been very strong and he is a reference point for his team-mates, it was a top-level performance."
Pekerman also reserved mention for star winger Rodriguez, who has stepped up in the absence of the injured Radamel Falcao to score in both of Colombia's opening two World Cup games.
"He has reached the very highest standards among players with his characteristics," added Pekerman.
"He is mature, he has commitment, he can finish, he has vision, he can shoot and today he scored with a header to add something else to his technical qualities."
