Colombia line-up irrelevant, says Zuniga
Colombia will make their maiden quarter-final appearance at a FIFA World Cup on Friday when they face the host nation in Fortaleza.
Jose Pekerman's Colombia side are one of four teams in the last eight that have won all four of their matches in Brazil with the Argentinean coach having largely settled on his preferred XI.
Apart from Colombia's final Group C encounter against Japan - when they had already qualified for the round of 16 - Pekerman has picked close to identical starting line-ups throughout the tournament.
David Ospina has been the Argentine's preferred goalkeeper with a back four of Zuniga, Cristian Zapata, captain Mario Yepes and Pablo Armero in front of the Nice gloveman.
Carlos Sanchez and Abel Aguilar have anchored Colombia's midfield with James Rodriguez ahead of them, while Juan Cuadrado has started on the right and Teofilo Gutierrez has played up front.
Ibarbo was Pekerman's preferred player on the left wing at the start of Brazil 2014 but after Martinez scored a brace versus Japan the latter was also given the nod in the round of 16 against Uruguay.
Reports in the Colombian media have been split down the middle as to whether Pekerman will opt for the greater work-rate of Cagliari winger Ibarbo at the Estadio Governador Placido Aderaldo Castelo or prefer the superior goal-scoring threat of Porto striker Martinez.
But Zuniga is convinced that whoever plays for Colombia will be committed to Pekerman's strategy.
"As I have always said it doesn't matter who is playing in the line-up and as Pekerman has said we always play with responsibility and the willingness to do the right things, while also enjoying," the Napoli right-back said on Thursday.
"The coach says to each player whatever we have to do and we try to do that.
"The main idea is going into the pitch and trying to play a final against Brazil but with responsibility on the field."
Both Zuniga and Pekerman underlined how tough playing Brazil in front of their home fans would be but the latter claimed he was not worried how the crowd might affect referee Carlos Velasco of Spain.
Brazil's opening win of the World Cup against Croatia was overshadowed by a dubious penalty decision that went in their favour, while Chile striker Alexis Sanchez claimed before his team played the home side that "what most worries me is the refereeing".
"In terms of the referee I always have the hope of he has good performance," Pekerman said.
"I don't have any suspicion and I don't think he will have any influence in the game."
The Argentine added: "We know there are mistakes in football from players, managers or referees but we trust in the good faith or credibility because all of them try to do their best."