"You need perfect referees, but where is the perfect referee?" said Clemente, who is attending the National Coaches Convention in Copenhagen run by Uefa, the governing body of European football.
Clemente, however, does not favour the introduction of technology as a means of reducing the chances of errors by referees, such as televised slow-motion replays. "In my opinion, technology must not come into football, because then the arguments will end and without arguments football will die," he said. "We would lose the great attraction of football, that a modest team can upset a big team."
Euro 96 suffered from several glaring mistakes, including an apparently valid "goal" scored by the Spanish striker Julio Salinas against England which was disallowed and a penalty awarded to the Czech Republic in the final against Germany for a foul which video replays showed was well outside the penalty area.