In Arsenal Analysis, tactical expert Michael Cox takes an in-depth look at what makes Barcelona tick, their danger men and playing style.
It doesn't take a genius to work out who Barcelona's three main goal threats are, but opponents have found it almost impossible to contain the terrifying trio of Luis Suarez, Lionel Messi and Neymar. All individually brilliant, they combine superbly too - now, they're even passing to each other at penalties.
The addition of Suarez means Messi has returned to the right flank, although he tends to drift inside into inside-right positions to orchestrate play, and is capable of devastating through-balls and chips over the defence with his left foot. Nacho Monreal will need to make good decisions about when to follow him inside, and be wary of Daniel Alves’ overlapping from deep.
Previously Busquets was a positionally-reliable holding midfielder and an unfussy distributor, but he's become much more ambitious and penetrative with his passing, especially now Barca can no longer count upon Xavi HernandezMichael Cox
On the opposite flank Neymar stays wider, although he also likes to check inside when taking on right-backs, and can bend the ball powerfully towards goal with his right foot. He should be involved in a direct battle with Hector Bellerin throughout.
Suarez is Barcelona's most prolific forward, but his role in the side is also about bringing the best out of the other two. He does this in two ways. First, he makes extremely intelligent lateral runs to drag centre backs out of positions, creating gaps for Messi and Neymar to dart into. Equally importantly, though, Suarez runs in behind repeatedly, which forces the opposition defence deeper and creates space between the lines.
This type of run isn't something Barcelona have always been able to rely upon in recent years. In fact, this current Barcelona format is essentially the opposite of the system Pep Guardiola used when Arsenal last faced Barca in 2010/11. Then, Messi was the false nine, starting centrally and moving deep, with runs in behind from the two wide positions. Now, Suarez is the central player and goes in behind, with movement inside from the flanks.
It's clearly been highly effective, but Barcelona no longer overload the central midfield zone, and are arguably less effective at involving the front three regularly. Well-organised sides like Atletico Madrid sometimes stifle Barcelona by preventing the ball being played into the front three in the first place, and that might be Arsenal's best approach.
There are two ways to go about that. Opponents can sit deep, a la Atletico, with the midfield forming a solid barricade in front of the defence, meaning Barcelona's forwards either have their space restricted, or have to come into extremely deep positions to collect the ball.
Alternatively, sides can press and harm Barcelona's passing build-up from deep positions. Over the past couple of months there have been occasions when Barca's passing in deep positions has been sloppy, and they'd turned over possession more readily than you'd expect.
This has been a particular problem in the opening period of matches, when the tempo is high. It feels like Barcelona take a while to get into their passing rhythm, and if Arsenal press in the first 10 minutes, they could cause problems.
The man who generally succeeds in gaining control of the game is usually Sergio Busquets, and Arsenal must watch him particularly closely.
Previously Busquets was a positionally-reliable holding midfielder and an unfussy distributor, but he's become much more ambitious and penetrative with his passing, especially now Barca can no longer count upon Xavi Hernandez. A particular trick is when Busquets turns on to his right foot, and opens up his body as if to play a pass out to Alves or Ivan Rakitic on the right wing, before instead cutting a penetrative ball into the path of one of the forwards.
It will probably be up to Mesut Ozil, who has faced Busquets many times before in Clasicos, to mark him. The last time Arsenal had a home match against a side of this calibre was the 2-0 win over Bayern Munich in the group stage, when Arsène Wenger notably praised Ozil for fulfilling his defensive responsibilities diligently. If Arsenal are to record another memorable win, Ozil will again need to excel.Copyright 2016 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source