Even though the number of entries showed no increase over 1966, the number of teams actually rose by one third! The qualifying matches for the 1970 competition encompassed the whole world for the first time, with a total of 170 matches being played involving 168 teams in every continent.

No fewer than half of the quarter-finalists from 1966 fell by the wayside in this hotly contested elimination round: Portugal found themselves in a group that would be won by Romania, along with the surprising Greek team and Switzerland, who finished last. Hungary, winners of the Olympic title in Mexico in 1968, had to go to a play-off against Czechoslovakia in Marseilles, which they lost by the wide margin of 4-1 - the first time that they had failed to reach the World Cup finals since 1950. While Korea DPR were disqualified for their refusal to play against Israel, Argentina were also eliminated, by Peru. Brazil and Uruguay made up the South American contingent.

A sad note was written into the history of the World Cup, when Honduras and El Salvador, between whom relationships had been hostile for several months, found themselves opposed to each other in a play-off match which ended in a bloody three day battle. After this regrettable incident it was El Salvador who qualified - they had played a total of ten matches.

In Africa the format started to change in the direction of its present form: knock-out matches at the start and then group games in the decisive stage. Morocco were the first African team to qualify for the World Cup finals by means of an internal African elimination round (Egypt had qualified without having to play a match in 1934.)