Format
The format of the competition changed from 1954: 16 teams still competed in four groups of four, but this time each team played each of the other teams in its group at least once, without extra time in the event of a draw. Two points were awarded for a win and one point for a draw. As in 1954, if the second and third placed teams finished on the same points, then there would be a play-off with the winner going through. If a play-off resulted in a draw, then goal average from the group games would have been used to determine who went through to the next round. If the goal averages were equal then lots would have been drawn. If the first two teams finished on equal points then goal average would decide who was placed first and second. These arrangements had not been finalised by the time the tournament started and were still being debated as it progressed. Some teams complained that a play-off match, meaning three games in five days, was too much, and before the second round of group matches FIFA informed the teams that goal average would be used before resorting to a play-off. This was overturned when the Swedish Football Association complained, ostensibly that it was wrong to change the rules mid-tournament, but also because it wanted the extra revenue from playoff matches.
This was the first time that goal average was available to separate teams in a World Cup, although in the event it was not used to eliminate any teams: all three playoffs finished with decisive results.
Read more about this topic: 1958 FIFA World Cup