Trailing 1-0 after the first leg of their Europa League clash with Chelsea, Sparta Prague will travel to West London on Thursday looking to pull off a major upset against the Blues.
We know where the main threat of the night will come from where Rafa Benitez's team is concerned, but what of the Czechs?
They currently sit third in the Gambrinus Liga, trailing rivals Viktoria Plzen by just three points. Their success this term has been based on a solid defence and midfield, conceding just 12 goals all season—the second-best record domestically.
But Sparta can cause problems offensively, too, and the Blues will need to keep a watchful eye on the Czechs' attacking instincts if they are to build on their victory in Prague last week.
Bleacher Report looks at three stars who could very well make Chelsea pay the ultimate price if the Blues are not at the races on Thursday.