Renato Sanches Cristiano Ronaldo Portugal
Renato Sanches and Cristiano Ronaldo will not be seen in the Rio Olympics 2016 for Portugal. Pictured: Sanches and Ronaldo during a training session, June 5, 2016Reuters

Portugal have not been impressive so far in this Euro 2016, and it is safe to say, neither have Poland, especially in an attacking sense. With goals and that ability to excite not quite hitting expected levels yet for either team, maybe a quarterfinal of Euro 2016 is the stage required for the likes of Cristiano Ronaldo and Robert Lewandowski to fire.

While Poland had to go through the penalty shootout to get the better of Switzerland in the last 16, Portugal eked out a 1-0 victory over Croatia, thanks to a 117th minute goal from Ricardo Quaresma. Neither of those matches will be in the "watch it over and over again" list of European Championship matches, with both teams struggling to find their goalscoring mojo.

Portugal looked like they might have finally hit their stride after a thrilling 3-3 draw against Hungary, but that proved to be a false dawn, because what followed was the most dire, boring football match of Euro 2016.

Fernando Santos will not worry too much about the quality of that particular match, however, because, Portugal, in the end, ended up on the winning side, which in turn set them on their way to Marseille to play in the quarterfinal against Poland. What will worry Santos, however, is the fitness of some of his players.

Left-back Raphael Gurreiro and midfielder Andre Gomes have not trained since Monday, missing out on the session the day before this big Euro 2016 quarterfinal as well. Santos said he will make a decision on his starting XI on the day of the match, with both players set to undertake fitness tests.

"There are some players who aren't 100% fit so we'll wait until (Thursday) to ascertain whether they are entirely fit or not and if they can play or not," Santos said during his media conference. "Sometimes the players can recover and we still have 24 hours to go."

Even if Gomes ends up being fit, Santos is likely to start with teenager Renato Sanches, who was like a breath of fresh air when he came on against Croatia. Sanches seemed to thrive on the big stage, rather than go into hiding, and he will definitely be one of the players to watch in this quarterfinal.

Another player hoping to bag the headlines will be Ronaldo, and having been frustrated in the match against Croatia – even if he played a big part in the winning goal -- the Real Madrid superstar will be desperate to make his mark against Poland.

As disappointing as Ronaldo might have been in Euro 2016 – barring one match – Lewandowski has been a touch more sub-standard. Poland are heavily reliant on Lewandowski's goals, as Euro 2016 qualification showed, but the Bayern Munich striker just hasn't been able to hit the target. With Arkadiusz Milik impressing but missing scores of chances, time is nigh for Lewandowski to score his first goal(s) of Euro 2016.

Poland do not have too many injury concerns, but Kamil Grosicki, one of Poland's most impressive players in this tournament, Lukasz Piszczek, Krzysztof Maczynski, Michal Pazdan, Slawomir Pezsko and Artur Jedrzejczyk are all in danger of missing the semifinal, if they get a yellow card. The Portugal players walking the yellow card tightrope are Pepe, William Carvalho and Ricardo Quaresma.

Confirmed starting XI: Portugal: Rui Patricio, Cedric, Fonte, Pepe, Eliseu; Silva, William Carvalho, Renato Sanches, Joao Mario; Nani, Ronaldo.

Poland: Fabianski; Piszczek, Glik, Pazdan, Jedrzejczyk; Blaszczykowski, Krychowiak, Maczynski, Grosicki; Milik, Lewandowski.