He was appointed to quarter-finals at both Euro 1968 and Euro 1972, and a semi-final at Euro 1968, as well as the opening group stage game between Mexico and the Soviet Union at the 1970 World Cup, which saw him become the first referee to show a yellow card in a match. He also refereed a second-round game at the 1974 World Cup. Thus he is the only referee that was nominated by the FIFA for three World Cups. In total he was a FIFA referee for 17 years, which is the record in FIFA history.