Cristiano Ronaldo v Jonathan Mensah
Cristiano Ronaldo has clearly struggled with his knee injury so far in this World Cup, as he has failed to demonstrate the the explosive runs and shots that have made him one of the best players of all time. That has visibly hampered him a great amount and prevented the 2013 Ballon d'Or winner from reaching his highest standard consistently.
However, the 29-year-old forward has shown it in flashes, and that was proven in the last-minute draw against the USA, when he delivered an outstanding cross that no defender could deal with. Portugal not only need to beat Ghana, but need to beat them by a few goals, therefore, Ronaldo will need to show more than flashes on Thursday if they are to progress to the last 16.
Jonathan Mensah played 34 times for Sunderland while on loan from Lyon between 2009 and 2011. The defender failed to agree a permanent move, though, and since has struggled to play at the highest level, as he is currently featuring for FC Nitra in the Slovakian league. His performances so far at the World Cup have been consistent, though, and have shown why he did have a long stint in the Premier League as well as Ligue 1 in France.
Ronaldo is likely to play on the left but will certainly have the freedom to drift inside as they will look for goals. With Ghana looking for goals too and likely to push players forward, Mensah could be isolated with Ronaldo.
Pepe v Asamoah Gyan
Pepe's qualities as a footballer are admired by many, but his temperament is something that many see as a big weakness - him headbutting Thomas Muller in the first half of their opening match against Germany was a clear example of that. Rightfully sent off, Portugal struggled without him and lost 4-0, with many blaming the Real Madrid defender for the defeat. He is now likely to return in defence, and will need to demonstrate his abilities as a footballer to show why he is admired by so many.
Asamoah Gyan relishes playing in the World Cup. After his goal during the 2-2 draw with Germany, he is joint top with Reggie Miller as being the highest goalscorer in the tournament for a country from Africa with five goals. No doubt he will be looking to break that record in this tournament, and there is a great chance this will be Ghana's last match of the tournament if USA and Germany draw in the other encounter. If he does score, then you can expect a celebration worthy of the achievement.
Joao Moutinho v Michael Essien
The AS Monaco midfielder loves to get himself on the ball and create chances. When he is on the ball in space, Portugal look a far better side than when he isn't on the ball. They struggle to get the ball forward quickly and accurately, and as a result allow the opposition time to get players back in numbers, especially to double up on Ronaldo.
With Sulley Muntari suspended, there is a great chance that Michael Essien will start his first match in this year's World Cup. If he does, then the former Chelsea midfielder will need to be aggressive in midfield and stop Moutinho from having the time to get his head up and pass the ball. If he can, then Ghana will stop Portugal at the source of most of their dangerous attacks and will feel confident that they can win this match. Essien will need to be as good as Muntari has been if that is to happen.