February 16, 2011 produced arguably the greatest night in Emirates Stadium history - when Arsenal beat Barcelona in the first leg of their Champions League last-16 clash.
Here's the story of a magical European night, as told by some of the key figures and fans around the world.
Arsène Wenger: It was unusual for us to go into a home game as the underdogs, but it took a bit of the pressure off. But we had a huge desire to win and viewed it as a good opportunity to show we were a different team to the previous year [when Arsenal lost 6-3 on aggregate to Barcelona].
John Cross, football writer for the Daily Mirror: The newspapers had signposted it from weeks out as it was such an exciting game. The anticipation was huge. There was a bit of spice in the air at the pre-match press conferences and Arsenal felt they had a chance - you could sense that from Arsène Wenger.
Cesc Fabregas: It was one of those games that don't come round very often, so when they do you just want to go for it. We knew we had to play with no fear even though we were facing the best team in the world, maybe even the best team in history.
Jack Wilshere: Before the Wolves game [four days prior] all the boys had been saying, 'Don't think about Wednesday' but it was hard at times. We knew we had to get in their faces, be a bit nasty and stop them playing.
Tim Clark, blogger for Arse2Mouse: I went around to a friend's house to watch the game. His lovely girlfriend made us some dinner but I was so nervous I couldn't eat any of it. I don't think I even drank anything - just water. I was like an expectant father from the 1940s outside a hospital ward!
Kylo Kelly, fan who attended the game: When I got to the Emirates, it felt like there was something different about the night and the atmosphere. Everyone seemed to really be pulling together.
Kick off: Almost immediately it is clear Barcelona are at their irresistible best. They dominate possession and while Robin van Persie has an early attempt, it is the Spaniards who look most dangerous with Lionel Messi missing two clear-cut opportunities.
Arsène Wenger: I accepted that Barcelona would have more of the ball than us - sometimes it's best to put yourself in the frame of mind knowing it is possible because then you are prepared to deal with it. If you are not prepared mentally it can shock you and take your confidence away.
Tim Clark: My Dad texted me to say, 'This looks ominous, it's coming'. It felt like one of those games where time dilates and slows down. The first half seemed to take an absolute age.
Finally Barcelona take the lead as David Villa races through and slots the ball under Wojciech Szczesny in the 26th minute.
Cesc Fabregas: They scored the kind of goal that Lionel Messi and David Villa are experts at creating and they also caught us with a couple of other one-on-ones - Messi doesn't usually miss those.
They scored the kind of goal that Lionel Messi and David Villa are experts at creatingCesc Fabregas
Half time: Messi has a goal disallowed before the break as Barcelona continue to dominate. Things don't look good for the hosts.
Arsène Wenger: At half time I told them it was important to keep their belief and push more on certain players because we gave them a bit too much room in the first half. I felt we could change the game, we had to remember the previous season when we came back in the last 20 minutes.
John Cross: Due to print deadlines, journalists often have to write a running match report at half time and that means some of it has to be purely based on what happened in the first half. As the game wears on, you top it up with more action at 60 minutes and then a little more at 80 minutes, and then your intro. It is very difficult, but Barcelona really were dominant at that point.
Second half: Arsenal are much improved with Van Persie again going close and a teenage Jack Wilshere the driving force in midfield.
Tim Clark: Jack was so good. There was always that sense that we have a 'diet Barca' version of playing, but the question was 'could we match them?' But he showed very quickly that he could live among what will ultimately go down as one of the best midfields in history.
Bacary Sagna, who watched from the stands: Barca used a lot of energy in the first half, they could not keep playing that way for the whole game so we knew there would be a moment when they would drop.
Finally Arsenal make the breakthrough in the 78th minute as Van Persie crashes home a magnificent volley from an acute angle.
Kylo Kelly: I don't think anyone was expecting him to shoot from there, it was just world class. I went absolutely crazy in the stands, in fact I jumped up and accidentally headbutted my granddad! He took it well fortunately; he was busy celebrating as much as anyone!
I went absolutely crazy in the stands, in fact I jumped up and accidentally headbutted my granddadKylo Kelly
Fernando Valenca, fan watching in Curitiba, Brazil: I got stuck in traffic on my way home from work and missed the first half. I didn't really want to watch the game because I was going to wait for a re-run of the full 90 minutes. But then I heard my neighbour - who is a Barcelona fan - screaming 'no!' because we had scored and I just had to watch it.
Tim Clark: I was running around the lounge, hugging my friend and his missus. I was swearing at the TV, it was amazing. The sheer audacity to take the shot on from that angle. There is barely a striker who would try it, let alone execute it.
John Cross: The problem when you have a fantastic side like Barcelona is that they seem invincible, there is an aura around them that make teams feel inferior to them. But when you score against them that mystique is taken away and the fans could feel that more than anyone. The atmosphere was so intense after the goal.
Five minutes later things get even better as a slick counter-attack ends with Andrey Arshavin sweeping in the winner from the edge of the area.
Tim Clark: There is nothing hyperbolic about saying that was a goal that if Barcelona had scored it, everyone would have been purring about it. Every touch in the move was perfect, they were all aware of where each other was, they all made the right decisions at the right time.
It was a goal that if Barcelona had scored it, everyone would have been purring about itTim Clark
Arslan Ali, fan watching in Islamabad, Pakistan: I was watching the game late at night and that was a dream goal. It was like everything had fallen in place. I just started screaming and woke everyone up in the house!
Fernando Valenca: When Arshavin scored I went to the window and yelled 'Yes!' just to spite my neighbour a little bit! It was one of those moments that you keep watching over and over again and you get goosebumps about.
John Cross: While there might have been eulogies being trotted out at half time about how good Barcelona were, in the second half it was much more balanced. When Arsenal scored twice, you could see frantic rewriting going on everywhere around me in the press box!
Full time: After an extraordinarily tense finale, the final whistle goes: Arsenal had beaten the European champions.
Cesc Fabregas: The atmosphere was definitely one of the best I have experienced at Emirates Stadium. The supporters were truly special - they kept us going and went crazy at the final whistle.
Fernando Valenca: When the whistle went, it felt like the sun was out and the flowers were blooming and it was spring all of a sudden because we had just beaten the best team in the world!
It was a night to show the whole world how fantastic football can beArsène Wenger
Xavi, Barcelona midfielder: The team made significant errors, but played good football. All we lacked was the finishing touch. We didn't convert our endless opportunities. The match was up for the taking, but we failed to win.
David Villa, Barcelona striker: We played a good game and created a lot of chances. But we were up against a great team in Arsenal who caught us on two counter-attacks and hurt us.
Tim Clark: There was so much adrenaline coursing through me that I sat up until 3am reading every single match report that was online, reading Twitter, watching the goals and the game again and again. I just could not sleep.
Arsène Wenger: We stuck to what we wanted to do, and that - as well as our mental strength and togetherness - was dominant to our success. Nobody showed any sign of dropping their focus. It was a massive night because everything clicked. Our fans were fantastic - like the players, they refused to give in. It was a night to show the whole world how fantastic football can be.