Whenever this many people care this much about anything, white Christians look to piggyback onto their passion with a good ol' fashion salvation message. In World Cup/Mission Trip mode, they'll frequently call this effort something like, "Kickin' for the Kingdom: World Cup 2010."
Every 4 years, American white Christians pretend to care about "the beautiful game" in order to use this global gathering as an evangelism opportunity. Unfortunately, their complete lack of knowledge about any current players or anything about sport in general instantly renders most conversion conversations with crazed fans moot.
As an attendee of the World Cup, if you see an American white Christian wearing a recently purchased replica soccer jersey and holding a Bible, be cautious in approaching this white Christian. He will joke that in American "fútbol," everyone can use their hands. This will naturally transition into how goalies use their hands to save their team. The topics of hands and saves having recently been brought up, the savvy white Christian will transition seamlessly into a conversation about a different type of "Savior" who used his hands to save the world. This entire monologue will have taken place assuming that you speak English.
With a Bible in one hand and a John 3:16 poster in the other, this rainbow-wigged white Christian will have additional key identification signs. It is likely that this white Christian will be attempting to set up games of street soccer in an attempt to draw the interest of children. Amidst any actual competition, this white Christian will also be toe-poking every soccer ball that comes their way with basketball shoes because that's the closest thing to soccer attire that they could find on short notice before they journeyed on this mission trip. Another key indicator- every American white Christian will cite Pelé as their favorite current player- not realizing that "the King of Football" stopped playing in 1977.