(Reuters) - Netherlands coach Louis van Gaal admitted he may be guilty of underestimating his own World Cup squad but said his players would not be making the same mistake with regard to their quarter-final opponents Costa Rica.

The teams meet at the Fonte Nova arena on Saturday.

Van Gaal told reporters on Friday the Dutch had brought "not a fantastic team but a team that is hard to beat" to the tournament in Brazil, prompting a question about perhaps undervaluing the potential of his own side.

"Maybe, yes; maybe but we had strong preparation before the World Cup and although we don't have the best starting 11, we certainly are among the best squads," he responded.

"By that I mean we have 23 players who are all pulling in the same direction. We support each other and the players compliment each other and that's why we have got some strong results here."

Before the World Cup, Van Gaal underplayed Dutch chances, repeatedly pointing out the inexperience in the squad. They one of the youngest of the tournament, with an average age of 26 years and 170 days.

GULF IN TALENT

"Some of our younger players have just as little experience as the Costa Ricans," he said when asked about a gulf in talent and exposure between a country who have been to three World Cup finals and the small central American country who have gone further in Brazil than ever before in tournament history.

"I am positive there will be no underestimating Costa Rica by my players. To get as far as they can in this tournament is what they want to achieve. They believe that this is the highest podium in world soccer and they are seeking to stand on it. They won't be underestimating any opponent."

The Netherlands return to the stadium where they thrashed world champions Spain 5-1 in their first game at the tournament, with Van Gaal hailing a major boost in confidence in the subsequent weeks.

"That is the biggest difference since we beat Spain. I've really seen the confidence grow as we finished top of our group.

"Mine is a team that will be fighting to stay in contention until the last minute at this World Cup and you will see the evidence of that in our next three matches ... but that you already knew," he winked at reporters.

To win the World Cup, the Dutch must get past Costa Rica, a semi final against either Argentina or Belgium in Sao Paulo on Wednesday and the final in Rio de Janeiro on July 13.