The Italian was downtrodden after the defeat marred his 20th appearance as manager for the 30th-ranked FIFA nation, which have now lost two of its last three matches.
With Europe-based players such as Borussia Dortmund's Shinji Kagawa returning to Japan as late as Tuesday, physical conditioning appeared to be the downfall of Samurai Blue as the team struggled to defend against Uzbekistan's well orchestrated counterattacks.
"We're sorry [about the outcome of the game]," Zaccheroni began the post match press conference by saying. "We wanted to do better, but when one loses, credit should also be given to the opponent. Uzbekistan were missing some of their starters, but they still showed how good a team they are.
"We did better in the first half, but they were better in the second half. Still we missed a lot of passes and they won all of the 50-50 challenges.
"Besides the goal and the counterattacks, they never gave us problems. Still they were very focused and aggressive and never gave us much time to think."
With players such as Kagawa and Shinji Okazaki hesitating to shoot throughout the night, Zaccheroni noted a need for his players to convert their chances.
"One thing we must improve are shots from outside the box," the manager pointed out. "Many times we had a free player outside the penalty area, but they always tried to get inside instead of shooting.
"[Takashi] Inui, Okazaki, Kagawa. They need to take some shots."
With no international dates before the final round of World Cup qualifiers begin on June 3, the former Milan manager hoped that his players would improve their conditioning.
"In these three months I just want my players to play as much as possible," Zaccheroni added. "The fact that part of our team is based in Europe is of course a difficulty that exists, but we need to learn to live with it.
"The teams we'll meet in the next round are almost all physically strong teams, so we need to be ready for that."
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