The South American side beat Japan 4-1 in Cuiaba to add gloss to a successful group stage that also included a 3-0 win against Greece and a 2-1 victory over Ivory Coast.

Pekerman, who led his native Argentina to the quarter-finals in 2006, said Colombia -- featuring at their first World Cup since 1998 -- were a "tight group".

"My players know that they have to play at a very intense pace. They need intensity, they need to concentrate on very little details. They must be able to play together, and they all have to be ready," he said.

Uruguay stand in the way of the best-ever showing at a World Cup for Colombia, whose last-16 performance in Italy in 1990 was the only other time they have made it out of the group stage.

That flair-packed team boasted the likes of Rene Higuita and Carlos Valderrama.

When asked whether his side could be the best in the country's history, Pekerman said he did not like comparisons.

"People remember that time because it was wonderful, it was beautiful, it was something very special and it proved what Colombia can do," he said.

"Our team is playing well, is playing at the World Cup after a long time. But I think we have to concentrate on what we do.

"We still have to improve, we still have to keep working hard. What's important is that we have very young players, and that's important in my opinion for a World Cup, because that means we have more potential for the future."

Pekerman said Uruguay would be a tough team to beat even though they could be without Luis Suarez, at the centre of a new biting storm.

"I haven't really analysed what we're going to do against Uruguay but I know we're going to face one of the biggest and most important teams in South America and in the world," he said.

"They always play well. They have a very good and rich history."

The teams will meet at the Maracana in Rio de Janeiro on Saturday.