The UEFA Champions League knockout stages are upon us and the finest 16 teams in Europe go head-to-head for one of the biggest prizes in football.
Here, we bring you a quick tactical lowdown on each of the remaining teams so you'll have an idea of who to look out for, what you're in for and what to expect.
Enjoy the slideshow!
Arsene Wenger's Arsenal rarely changes so we're well-versed in what we'll see here.
A hybrid 4-3-3 formation will need to use all its power in midfield to overcome an elite Bayern Munich centre, so expect to see Abou Diaby and Jack Wilshere in penetrative roles if fit.
Olivier Giroud will be used as a foil with Theo Walcott running off him; It's a system that's working very well in the English Premier League, but will Dante and David Alaba be fooled?
Barcelona, under Tito Vilanova, are a slightly more direct, attacking side than they were under Pep Guardiola.
He still favours the base 4-3-3 formation and tiki-taka style, but moves offensive pieces into more damaging positions quickly and the likes of Andres Iniesta and Cesc Fabregas are having unbelievable seasons.
If there's a concern, it's the defence, but will any team get hold of the ball long enough to punish them?
Jupp Heynckes' men look pretty much unstoppable right now as they waltz their way through the Bundesliga schedule.
The 4-2-3-1 formation crafted suits everyone's strengths down to the ground and and the interchanging and movement is second to none. Thomas Muller, Toni Kroos and Mario Mandzukic are all incredibly fluid players that make them tough to predict and stop.
A perfect combination of control and cutting edge.
Get ready for fast-paced, all-action football if you're planning to watch Borussia Dortmund.
Jurgen Klopp's charges are one of the most exciting teams in world football, utilising quick passing, overlapping full-backs and forward runs from midfield.
Celtic were an incredibly rigid side throughout the UEFA Champions League group stage and it's easy to see why.
They were stuck with Barcelona, Benfica and Spartak Moscow, meaning they faced scintillating football or harsh travelling conditions on a regular basis.
Expect the Bhoys to battle hard, fight right till the end and play almost exclusively on the break—they can hurt teams and La Blaugrana can testify.
There are more questions hovering over Galatasaray than answers.
With star striker Burak Yilmaz scoring for fun, how does Fatih Terim contemplate fitting Didier Drogba in?
Does Wesley Sneijder come in to partner Selcuk Inan, and will the formation be a diamond to use the Dutchman as a No. 10 or a flat-four midfield?
What of the returning Emmanuel Eboue?
Antonio Conte will roll out his impressive 3-5-2 formation and welcome back some important players to his side.
Andrea Pirlo utilises the regista role in the midfield and has two shuttlers—usually Claudio Marchisio or Arturo Vidal—either side of him to run the channels.
The formation lives and dies by its wing-backs, so lucky for Conte they nearly always get the better of their opponents. Could Kwadwo Asamoah make an immediate return on the left?
Mirko Vucinic is the vital link between the attack and the midfield and virtually plays as a nine-and-a-half.
Malaga's hopes in this competition will be pinned on wonderboy Isco, but in truth Los Boquerones have threats all over the pitch.
They'll use a 4-2-3-1 with Isco in the No. 10 position, but watch out for Joaquin, who's enjoying a renaissance season, and Eliseu, whose Kwadwo Asamoah-esque approach to the game is thrilling.
Finally, keep an eye on one of the best up-and-coming holding midfielders in world football—Ignacio Camacho.
Tactically, Manchester United are tough to predict.
Sir Alex Ferguson is expected to make specific changes to counter the threat of Cristiano Ronaldo at the Santiago Bernabeu, but on the whole they're a delightful attacking outfit.
They play an incredibly loose 4-4-2 with what looks like two nine-and-a-halves at times; Robin van Persie and Wayne Rooney have forged a world-class partnership and dip in and out of the forward line at will.
Expect the Red Devils to flood the box when going forward with any number of players.
The addition of Mario Balotelli has inspired Milan, but the Italian is cup-tied and can't take any further part in the UEFA Champions League.
Still, his arrival has rubber-stamped Massimiliano Allegri's faith in the 4-3-3 formation and it's only become more fluid thanks to the confidence Balotelli inspires.
Milan essentially play with three strikers, and M'Baye Niang's excellent form has seen the Rossoneri become far less lopsided in favour of Stephan El Shaarawy.
OK, so we're not going to see David Beckham at the Mestalla, but the hype around Paris Saint-Germain continues to grow.
Carlo Ancelotti has been trying out the ol' 4-2-2-2 formation in recent weeks to great effect and will likely carry it into the UEFA Champions League, meaning a holding pivot of Blaise Matuidi and Marco Verratti and a free-moving duo of attacking midfielders.
This formation has allowed the attacking peripherals to wow us while the side remains defensively solid. This is a must-watch.
Vitor Pereira favours the all-action 4-3-3 that has become the staple of Portuguese football in recent years.
Joao Moutinho and Steven Defour are perfectly suited for this, while James Rodriguez and Silvestre Varela represent perfect inverted threats from the wide area.
Jackson Martinez has surprised many by slotting in and taking command of this forward line in the absence of the star names sold.
Do not underestimate FC Porto.
Jose Mourinho favours his 4-2-3-1 but in practice it's a little more lopsided than most.
Cristiano Ronaldo drifts inside as a left forward in search of the ball and shooting positions, so less of a burden is placed on the No. 10 for Los Blancos.
The creative engine room is Xabi Alonso, who dictates from deep, while Sami Khedira is proving to everyone what an astounding box-to-box midfielder he can be.
It has to be said: Schalke are flailing.
Huub Stevens' sacking has done nothing, and losing Lewis Holtby in January is a big problem for Jens Keller to deal with.
Jefferson Farfan and Julian Draxler are now Die Koenigsblauen's main attacking threats slotting into the wide positions on a 4-2-3-1/4-1-4-1. Given their current predicament, they're a little tough to read.
Shakhtar Donetsk are another team who play some scintillating stuff, and there have particular players to watch out for.
Set out in Mircea Lucescu's 4-2-3-1 formation, Fernandinho is an absolute battering ram breaking forward from the No. 6 position, while Henrikh Mkhitaryan carries as much of a goal threat from the No. 10 position as any striker the Hirnyky field.
Darijo Srna—one of the world's best crossers—is an expansive full-back who links well with the industrious Alex Teixeira, and it'll be interesting to see if Taison can fill Willian's boots.
Valencia went almost unnoticed during the UEFA Champions League group stage, but were only just beaten to top spot by Bayern Munich.
Mauricio Pellegrino favoured the safety of the 4-2-3-1 formation but lost Fernando Gago in January. The Argentine wasn't performing in the league, but impressed many during his outings on the continent.
Lucky for the manager, Sofiane Feghouli—the midfielder I just can't work out (with regards to style)—is in solid form, and Andres Guardado provides a dynamic, vertical threat on the left.