Los Cafeteros secured a 4-1 win over Japan on Tuesday with two goals from Jackson Martinez and strikes from James Rodriguez and Juan Cuadrado confirming the three points despite Shinji Okazaki's goal.
Pekerman expressed his delight at how Colombia has performed in Brazil as its 100 percent record earns it progress to the knockout stages and a clash with Uruguay.
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"I'm happy because the team worked a lot," the 64-year-old Argentine told reporters after the game. "This is the result of work and patience of all the players and a whole country's support.
"This is a reward for Colombians - I always have felt Colombian."
Pekerman also reflected on their upcoming game against Oscar Tabarez's Celeste, who only confirmed their qualification for the next stage of the competition after defeating Italy 1-0 on Tuesday.
"[Uruguay] will be a very tough opponent," he added. "Uruguay is a team renowned in world history and really can play. But we are confident and we want to move forward."
Pekerman referred to Colombia next opponent and said the meeting on Saturday will be a "heads up" against the selection "Uruguayan".
"It's a very tough opponent, we knew it could happen, (Uruguay) is a great team, with history, today and is a very tough opponent, but we have a lot of confidence and that will be a head to head game," said Argentine, who for this game made several changes to the roster.