Fallen giants? While a reprieve exists in the form of a Europa League berth for third place, a number of Europe's biggest clubs won't be satisfied if they don't advance in the Champions League. However, most likely a few of the top teams in the competition will find themselves in Europe's second competition after rough runs on the biggest stage. Liverpool is already under fire at home, but their continental form has placed advancing out of their own hands, while defending champions Barcelona could easily fall out of Champions League contention as hard-charging Rubin Kazan pushes them in Group F. Even Real Madrid and Milan are sweating as Marseille keeps things close. Which big club has the most at stake in the Champions League should they fail to win this week?

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