Roberto Martinez believes the weather conditions in Brazil have been a major factor in the high-scoring start to the World Cup.
Forty-nine goals have so far been netted in the opening 17 games of the tournament.
And Martinez says that level of final third activity is because managers and players are still coming to terms with how to pace matches in the heat and humidity of the South American country.
Martinez said: “Very few European players have ever played in South America. Every coach here has done what he can to simulate the conditions but, however detailed their preparation, players can never be certain how they will react physically to the intensity of a full match here. That sows a seed of doubt.
“They may feel fine after half an hour, but they do not know how they will feel after an hour, after 80 minutes. That means they are unsure how to pace themselves. Some burn out - even those who do not start to conserve energy earlier than they normally would.
“That may explain why we have seen so many games where the team that takes the lead has gone on to lose. Teams are not quite sure how to play, how to control games, what is required physically, in an unfamiliar environment.”
The highest scoring game of the tournament so far was Holland’s surprise 5-1 demolition of Spain on the second day of the tournament.
The reigning world champions are back in action on Wednesday when they face Chile, who beat Australia 3-1 in their Group B opener.
Martinez says his homeland are now in a position with no margin for any further errors if they want to avoid an unforeseen early exit.
“Few would be surprised if Vincente Del Bosque made stark changes to his side after their disastrous defeat to Holland in their opening game,” continued the Everton manager.
“The manner of that loss left Spain facing a raft of questions. Some concerned players. Others centred on the style, on whether Spain need to abandon the principles that have brought them so much glory in the past six years.
“Del Bosque, though, will not allow emotion to cloud his thinking. He will know that Spain did not play well, and that when they do not play well they will be accused of lacking fitness, intensity and hunger.
“But he will also know that none of those accusations are correct. Del Bosque knows his players. He knows this is a squad that has always been motivated by targets: to win the European Championship, then the World Cup, then to become the first side ever to claim three major tournaments in a row. Now their aim is to break Europe’s hoodoo in South America. He will stand by his players as he stands by his style.
“But there is little room for error. Spain must win this evening, and do so against the sort of side they will not want to face, if they are to stand any chance of fulfilling their ambitions.”