After Manchester City's Martin Demichelis' certain red card against Barcelona, here are four which also took place in the biggest of fixtures...
Few could argue with Demichelis red card against Barcelona last night, even if the award of a penalty in itself was a contentious decision.
For City, to play out the remainder of the game with 10 men was a thankless and fruitless task, and many a side would have crumbled to lose by more than the two goals.
Champions League matches involving Premier League clubs in the knockout stages of the competition have seen a number of crucial red cards over the past three seasons, with differing levels of damage done.
Here are four which have have come in dramatic circumstances against Europe's top sides...
Robin van Persie: Barcelona v Arsenal 2011
Van Persie described the red card as a 'total joke' and it was an assertion nearly all Arsenal fans will have concurred with. As the game in the Nou Camp began it's second half, Van Persie was handed a second yellow card and subsequent red for the trivial offence of having a shot on goal after being flagged offside. The Dutchman claimed he had not heard the whistle amid the crowd noise. Arsenal were 3-2 up on aggregate at the time, but the task of holding out with 10 men was too great and Barcelona went onto win 4-3.
Rafael: Manchester United v Bayern Munich 2010
Tasked with coming back from a 2-1 away deficit, Manchester United had raced into a a 3-2 aggregate half-time lead. Bayern were on the ropes in front of a baying Old Trafford crowd, until defender Rafael da Silva was shown a red card in the 50th minute for a second bookable offence for a foul on Franck Ribery. United were forced to decamp into their own half as the game went on, and were ultimately undone by a precision volley from former Chelsea may Arjen Robben to bow out on away goals.
John Terry: Barcelona v Chelsea 2012
The Chelsea skipper's sending off was the rare case where his team were not cost dear. With Barcelona levelling the tie up at 1-1 on aggregate, Terry needlessly decided to knee Alexis Sanchez in the back, who made the most of the incident. Improbably, with a makeshift defensive pairing of Jose Bosingwa and Branislav Ivanovic, Chelsea held on, thanks in part to a missed penalty from Lionel Messi. They responded instantly through a Ramires goal, before Fernando Torres put the game beyond doubt in injury time. Chelsea went onto lift the trophy, led by Terry in full kit despite watching the final from the stands.
Nani: Manchester United v Real Madrid 2013
What would prove to be Sir Alex Ferguson's final Champions League game as manager, was also the one which made him the most angry. United were leading 2-1 on aggregated against Real Madrid when the Portuguese winger was handed an instant red card for a high tackle on Alvaro Arbeloa. While Fergie fumed in the stands, Jose Mourinho made instant substutions and tactical changes which helped him win the midfield battle with United losing their heads. Substitute Luka Modric equalised minutes later, and Cristiano Ronaldo bagged a winner to defeat his former side on home turf. There was no question that like the Bayern defeat the red card changed the game and United could only wonder what may have been.
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