Japan got their campaign under way with a 2-1 defeat to Ivory Coast and followed that result up with a goalless draw against Greece in Natal, but they remain in the hunt for a qualification spot.
Colombia lead the group on six points, three ahead of Ivory Coast and, although Jose Pekerman's side are already guaranteed a place in the second round, they could yet surrender top spot.
Japan are their opponents at Arena Pantanal on Tuesday and, while Alberto Zaccheroni's talented squad have not lived up to expectations, Zapata has told his colleagues to expect a tough match.
"We must think only of the next game," he told reporters. "We cannot worry about other opponents even when we face Japan's strong national team, which has great players.
"We cannot delude ourselves. Their team has a lot more quality than their results have shown. They have a lot of speed and tactical discipline. It will be a great game.
"(But) we have a course of action for each opponent we face. We have not had a final conversation with our coaching staff (yet), but certainly they have prepared something.
"We need to continue with the same humility to continue advancing."
Porto forward Jackson Martinez believes that the hot weather and humidity could give Colombia an advantage in Cuiaba on Tuesday, but he is certain Japan will push them until the very end.
"I think the weather will play a key role," he added. "But what causes upsets in football is how well you play. So whether it is hot or cold it is important that we concentrate on our game plan applied by the coach.
"Japan is a strong team physically. They are players that have been characterised by giving everything until the end, so we must focus on continuing the good work that we have done."
