Playing against the reigning champions, Chelsea's victory was also sweet revenge as they beat a Barcelona side that has troubled them incessantly in the past. Now Barcelona have to be asking what went wrong.
The answer is simple.
Barcelona are far too dependent on the play of Lionel Messi. In three straight huge games, Messi has failed to find the back of the net. His play has generally been poor for the past few games.
Perhaps most importantly, he is cracking under pressure.
Lionel Messi has not been clutch lately. He's squandered opportunities, taking 13 shots in the last three games and failing to score with any of them. Real Madrid was able to hold Messi to a single shot. Worse still, Messi missed a spot kick in second leg of the Chelsea match up that could have decided the tie. Another big penalty, another miss from the Argentine. Just like his penalty chance against Sevilla in October, he failed to convert when Barca needed it the most.
Messi has missed seven of 34 chances from the spot for a conversion rate of 79.4%. That's absolutely dismal.
Messi might be one of the world's best finishers and players, but he has failed to score from the penalty too many times for Barcelona to continue calling upon him.
It's time to give someone more reliable a chance.
Messi's poor play, however, isn't just a reflection on himself. Barcelona are entirely too dependent on their false nine. Many fans consider Arsenal overly reliant on Robin van Persie to score, and rightly so considering he accounts for 40% of his team's goals. Messi accounts for 43% of Barcelona's.
On top of that, Messi is also Barcelona's top assist man, tied for second in La Liga with Real Madrid's Angel Di Maria and behind Mesut Özil. You might think it's fantastic that the little man is able to score so much and still contribute to his team, but it raises a big question: What happens when Messi underperforms?
The last string of matches have made painfully obvious that Barcelona cannot rely only on Messi. He's scored over 70% of his goals at home and picked up over twice as many assists from Camp Nou. On the road, he is relatively poor and by extension so is Barcelona.
In today's match, Messi was less than his best.
He didn't have a bad game, but he wasn't the player you need in a big match against one of England's best sides. He completed 74% of his passes, a much lower rate than his usual 84%. He picked up a foolish yellow card and, of course, could not score despite so many chances. He has no excuse for not finding the back of the net against a ten man side. He has no excuse for failing to score from twelve yards away. Chelsea's core defenders were not even in for half the game, and still the backups were able to stop Messi.
Obviously in the last three matches, Barcelona was able to score even when Messi didn't. That doesn't change anything. The fact of the matter is, when Messi plays poorly, so does the rest of Barcelona.
With only the Copa del Rey left to win, Barcelona might of learned a lesson far too late.