5 biggest upsets in the group stage of the Champions League

#5 Barcelona 1-2 Rubin Kazan: 2009/10

A full-strength Barcelona side were defeated by Kazan

This is the biggest upset in UEFA Champions League history, not only because of the difference in the calibre of both the teams, but also the fact that Barcelona fielded their best 11, while Rubin had a couple of players sidelined due to injury. With Zlatan, Messi, Pique, Iniesta, Xavi and Toure all starting, Barcelona was expected pick up an easy win over the Russia-based side, Rubin Kazan.

(Video Courtesy: carlos8583 YouTube Channel)

Ryazantsev shocked the world by scoring in just 2 minutes but in the second half, Zlatan Ibrahimovic equalised and it stood at 1-1. Barcelona dominated the match, but the Russians managed to score in the 75^th minute on the counter, to steal a 2-1 victory. Just two weeks later, these two sides met again in a game that ended in a goalless draw. Nevertheless, Barcelona went on to top their table, with Rubin Kazan finishing third.