Will Portugal qualify for the World Cup if they beat Switzerland?
Cristiano Ronaldo is looking to follow up Euro 2016 glory with a World Cup title
LIONEL MESSI'S trials and tribulations during a turbulent World Cup campaign have been well documented.
But it is less well known that rival Cristiano Ronaldo has also yet to book his place in Russia.
Portugal go into their decider against Switzerland tonight in second place in Group B.
What do Portugal have to do to qualify?
Portugal were beaten 2-0 by Switzerland in the opening qualifier, and since then neither side has blinked.
The Swiss have won every single one of their nine matches, while Portugal have been victorious in all their eight matches since the defeat in Basel.
That means Switzerland are three points clear at the top of the group, but by virtue of a superior goal difference, a win will see Portugal claim top spot.
Anything other than a Portuguese win will see Switzerland top the group and Fernando Santos' side consigned to a play-off place.
Who could Portugal play in a play-off?
Greece (if they beat Gibraltar), Northern Ireland, Sweden and Republic of Ireland are likely to be Portugal's potential opponents in any play-off.
The European champions would be seeded for the draw based on Fifa rankings.