The 42-year-old has a plan up his sleeve to get the better of the South American side, but has refused to reveal exactly what he has planned until the game kicks off
Both teams harbour hopes of reaching the round of 16 at the other side's expense, although it remains possible that both can progress should Brazil unexpectedly lose to already-eliminated opposition Cameroon.
Kovac's men know that a win is the only way to guarantee progress to the knockout stages and is fully focused on avoiding leaving Brazil early. He has devised a secret plan to see Croatia become the first team to score past Mexico and in-form goalkeeper Guillermo Ochoa in this tournament.
“It wouldn’t be a failure not proceeding to the round of 16, but I’m not even thinking about that," he told reporters. "We will enjoy or football tomorrow.
"Mexico have played very well since Miguel Herrera took charge, but we have a formula for them, although I’m not going to reveal it yet.
"Ochoa is a great goalkeeper, but we have good forwards who will be a menace for him. If anyone have their knees shaking, it's Mexico."
Mexico were drawn in the same group as Croatia in 2002 and a 1-0 defeat to the Concacaf nation helped to seal their elimination at the group stage although Kovac, who played in that clash, insists revenge is not on his mind.
"I remember that game clearly," he added. "I remember Rafa Marquez who is still playing now and played then too, but this is not a revenge game because it’s been 12 years since then."
The final Group A clashes kick off in Recife at 22:00CET, with the two qualifiers to face either Chile or Netherlands in the last 16.