Fitness the focus for Zaccheroni
Zaccheroni's men were uninspiring in a 1-0 win over Cyprus in an international friendly last week, with Atsuto Uchida's 43rd-minute strike sparing their blushes.
Japan have come in for criticism in the wake of that performance at the Saitama Stadium ahead of the World Cup, where they will face Colombia, Greece and Ivory Coast in Group C.
Speaking before Monday's match against fellow World Cup participants Costa Rica in Florida, Zaccheroni said results were not important at this stage of Japan's preparation, with the Italian boss determined to get minutes into the legs of star men Keisuke Honda and Shinji Kagawa.
"If you have looked at some of the other teams' friendlies, this is the moment we focus more on the physical condition (of the players)," Zaccheroni told reporters.
"Try to get as many minutes under our players' belts, instead of thinking about the game and the final score."
Zaccheroni added: "Honda and Shinji Kagawa haven't played much recently, so yes they need to play. The thing I said before is of course related to Honda and Kagawa.
"I am not saying they will play 90 minutes (against Costa Rica), but I will try to keep them on the pitch for as long as possible."
Meanwhile, Japan attacker Honda said there is a fine line between success and failure as the country attempt to make their mark at the showpiece event.
Japan breezed through the Asian qualifying section, attracting plenty of admirers for their possession-based brand of football which sees them considered a dark horse to progress deep into the tournament.
And the AC Milan man knows their campaign in Brazil could come down to the most minute of details.
"I have many things to give back to the team. In order to win a tournament, the team needs to not only live up to their potential, but the atmosphere in the squad and the character of each player," said Honda, who is set to appear at his second World Cup.
"Those tiny factors can affect if they win or not, which is what I experienced at my club (this season).
"So I'll be mindful to sense any small changes to the team so that I can contribute to a good atmosphere and lead them in a good direction."
Japan face Ivory Coast in their opening World Cup game in Recife on June 14.