One name above all concerns Sporting and the fans that will be crowded into the Estadio José Alvalade on Wednesday night; that of Lionel Andres Messi, author of 12 goals in nine games and the main threat to any opposing team.
Jorge Jesus and his team will try to limit the Argentinian striker's influence and they will have taken note of the path Girona coach Pablo Machin followed just four days ago.
The way in which Pablo Maffeo shackled the Barcelona No.10 throughout the Catalan derby will give Jesus the opportunity to field Rodrigo Battaglia in a similar role.
There are no tickets left for the Blaugrana's first visit to the Jose Alvalade since 2008 and no less than 50,000 lions will be in the stadium where Cristiano Ronaldo began to build his legend.
They will be roaring on their team in the hope of springing a surprise in a group that on paper everyone expects Barcelona and Juventus to qualify from.
Sporting are an outsider, but they will aim to take advantage of their good start (3-2 over Olympiacos) against Messi and Co.