A recent three-game barren run saw the 24-year-old criticised by some sectors of the Spanish media, but Zubizarreta believes there was never any issue.
"Messi makes fewer mistakes than any other player," the 126-cap Spaniard was quoted as saying by Sport.
Zubizarreta also confirmed that summer signing Alexis Sanchez would be available for Tuesday's trip to the Czech Republic to face Viktoria Plzen in the Champions League.
"The doctors have told us that he can be in the squad," he said.
Messi, meanwhile, responded to his critics by netting a first-half hat-trick in Saturday's 5-0 victory over Mallorca and the Argentine will be looking to score his 200th Barca goal on Tuesday.
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