The Asian champions have been paired with Colombia, Ivory Coast and Greece in an even-looking Group C in Brazil, their fifth consecutive appearance at the finals. (Agencies)
"If we can play to the best of our ability then we can be a threat. I am confident," Italian Zaccheroni said after the draw in December.
"Obviously getting off to a good start is important," he said.
Japan made a quick start to qualifying and were the first side to book a berth in Brazil with playmakers Shinji Kagawa and Keisuke Honda the architects of some silky play, but defensive issues were exposed along the way in a shock 2-1 loss in Jordan.
Three defeats followed at the Confederations Cup last year but they won many plaudits for their attacking play in a 4-3 loss to Italy and 2-1 defeat by Mexico after opening with a 3-0 defeat against hosts Brazil.
Zaccheroni called on the Japanese Football Association (JFA) to find similarly testing fixtures for his charges to prepare them for the demands of a World Cup campaign and they duly obliged.
Attacking flair was again on show in the 4-2 home loss by Uruguay in August, where Diego Forlan and Luis Suarez flourished against Japan's soft-centred back four, who lacked pace and protection.
Zaccheroni has flirted in friendly matches with a 3-4-3 or 3-6-1 formation but seems set to employ a 4-2-3-1 for Brazil which would allow Atsuto Uchida and Yuto Nagatomo to attack from the fullback positions.
Neither, though, featured in Japan's most impressive result, a 3-2 win against a highly regarded Belgium in November which turned heads coming days after a 2-2 draw with Netherlands.
Yoichiro Kakitani has emerged as a talented forward more than capable of creating as well as taking chances, and he scored in Brussels.
He should get playing time in Brazil along with another newcomer, Yuya Osako, and the returning Yoshito Okubo although the experienced Shinji Okazaki is likely to claim the starting striker spot.
Central defender Maya Yoshida has struggled for appearances with English club Southampton this year but had one of his more impressive outings against Belgium alongside Masato Morishige in the heart of the defence.
They were ably supported by 23-year-old Hotaru Yamaguchi, who took on the role of midfield protector, but whether his display was good enough to convince Zaccheroni to drop his trusted lieutenant Yasuhito Endo for Brazil is another matter.
Likewise, Yasuyuki Konno has been Zaccheroni's favoured defender even though the Gamba Osaka man has struggled to repay the Italian's faith with shaky displays for club and country.
Japan, with their attacking style at the forefront, are sure to be more entertaining than in their previous World Cup appearances, but may lack the defensive capabilities to be as successful in Brazil.
The Asian champions have been paired with Colombia, Ivory Coast and Greece in an even-looking Group C in Brazil, their fifth consecutive appearance at the finals.