Yeah, there's something fascinating in the way the captain of a rugby team which is winning 75-3 will most probably sneak under an ord of screaming, 120-kg wild boars willing to kill him just to not let them score a goal in the last 5' of the second time.
Generally speaking (I've been an athlete and am currently a professional trainer and performance engineer), where a lot of money goes around there are always agreements under the table to let everyone earn their share. There are usually some rotations ("turns"?) which depend on the (social, political, economical) power of each firm/team owner.
For example, in the last 20 years a soccer team which had just been listed on the stock market has (almost?) always won the Italian A-league championship.
As for world soccer championships, there're probably not as many economical interests as in the leading A-leagues worldwide, so chances are that they cheat just a little here and there. But there are for sure rumors about European teams which have offered African teams money to let them pass the first round.
Professional sport is a business, is a show, and is a job. There's no linearity or consequence between the kids training in a ballpark and any professional league.
