The South American nation survived a late scare to chalk up their second win of the tournament against Ivory Coast on Thursday and secure a place in the knockout rounds.
But the game is not a dead rubber for Japan, who can progress with victory so long as Greece prevent Ivory Coast from taking three points.
In any case, Zapata insists he and his team-mates would be foolish to start thinking of the knockout stages already.
"You have to think game by game," the AC Milan defender told a press conference.
"Japan is a strong team and have good players. It is a tough game for us."
One Colombian player with a valuable perspective on how important it is to retain the winning habit is veteran back-up goalkeeper Faryd Mondragon.
Mondragon was part of the highly rated Colombia squads that bowed out at the group stages of the 1994 and 1998 World Cups.
The oldest player at the tournament celebrated his 43rd birthday on Saturday and is happy to see the new generation making impressive strides.
"I am privileged to be here with my 43 years," he told reporters.
"The hunger for glory of this group has been wonderful.
"We have a very tough test against Japan."
