Germany bolstered their back line with the return of central defender Mats Hummels on Thursday but lacked penetration at the other end of the field as they were held to a 0-0 draw by Poland at Euro 2016.
Portugal entered the Euro 2016 quarter-final after defeating Poland 5-3 on penalties in Marseille on Thursday.
Poland midfielder Grzegorz Krychowiak urged his team mates not to get carried away by their first ever victory at a European championship finals against Northern Ireland at Euro 2016 on Sunday. The 1-0 victory in Group C was the Poles' first win in seven games at the finals. It put the country in a strong position to reach the knockout stages as they prepare for a tough clash with world champions Germany in Paris on Thursday. But Krychowiak said: "We understood that the first match is very difficult, we were prepared for that. The next matches will show that we can be even better and go further. "We can do a lot, but we shouldn't be overly optimistic, having only won the first match. We should take it calmly with a cold-headed approach. We need to run our socks off, but I'm not hiding the fact that we want to win it."
Germany and Poland edged closer to the Euro 2016 knockout stage after playing out the first 0-0 draw of this year's tournament at the Stade de France on Thursday. The result means both teams have four points in Group C ahead of Northern Ireland, who have three after their 2-0 win against a Ukraine side who are still without a point and cannot now qualify for the last 16 at the finals.
Poland have an impressive defensive record at Euro 2016 but standing in their way to a semi-final spot is arguably one of sport's greatest-ever athletes, Cristiano Ronaldo.