Portugal are second in group A of the 2022 FIFA World Cup qualification series, a point behind Serbia who have played a game more. Cristiano Ronaldo's country will hope to avoid the damning European playoffs.
Portugal will play Republic of Ireland this evening and play Serbia in Lisbon later on November 14, should they win both games, they will qualify directly from Group A but if they fail to win the group, they will be drawn in the playoffs.
Many European clubs try to avoid the playoffs as it is a two legged home and away match that could go anywhere and have any consequences which could be unfavourable so they ensure they win their groups.
The match against direct competitor Serbia at home is what gives Portugal the edge. It means they have their own destiny in their hands. If they beat Ireland tomght, a draw would be enough to get the job done next week.