A rare European clash between the two sides who have a duopoly on the Premier League since 2004, but have only met in the Champions League once during those six years. The Moscow final is painfully remembered by Chelsea fans and the quarter finals gives the Pensioners a chance to avenge for the missed opportunity.

But revenge is not the most important prize. A place in the semi-finals of Roman’s Holy Grail awaits, possibly [more than likely] against relative minnows Schalke 04 after the German side (who currently sit eleventh out of eighteen in Bundesliga, five points off the drop zone).

4-4-2 V 4-4-2
Last time Chelsea faced Manchester in March it was Ancelotti’s men who emerged victorious with Lampard and Luiz’s first Chelsea goal securing the points and condemning United to what was only their second loss of the season.

That game was noteworthy for it’s relative openness between two top sides – considering that it’s often a ‘safety first’ measure adopted – as Mancini would surely agree is perfect.

Both played open 4-4-2’s, which reduced the game to 1v1 battles which, on paper, you would expect Chelsea to win (but that’s probably just me). The key to that win, at the time, was attributed to passion rather than tactics, and pressing. The two evenly matched sides (tactically) meant it was easier to press across the pitch, which Chelsea did to great effect. Luiz and Terry learnt the lesson that day of how pressing must be systematically consistent, or quality players can punish you – as Rooney did. However the flip side of this was that United slipped up twice after the break and Luiz and Zhirkov capitalised. The pressing lead to being vulnerable on the counter attack, which was neutered by the pace of Luiz. However he is ineligible for this match and so by way of association it is assumed Bosingwa will take the right back spot, next to Ivanovic who will man his central position.

While there is talk of Bosingwa’s probable inclusion as a real weakness, it can some ways be a real gold mine. The Chelsea 4-4-2 is an asymmetrical shape as Ramires is naturally drawn inside as a wide midfielder, where Malouda is a winger. If, as Osman did for Everton in the FA Cup, the opposition player tracks the runner inside, it can lead to exploited space on the wing. Bosingwa could move into a dangerous crossing position, but it must be remembered that Rafael could do the same thing. Therefore it may be worthwhile starting Anelka ahead of Torres or Drogba, as the Frenchman drops deep and this natural attribute could cover Chelsea deficiencies. Then a second half switch to either Torres or Drogba could punish a porous United defence which is running on fatigue and has relative inexperience in Smalling.

KEY ZONE
The midfield will decide the game. Chelsea’s midfield can outclass United’s on any day, but it’s a question of who turns up. If Ferguson does deploy a 4-5-1, as he regularly does on big occasions, then the three in the middle will have a spare man against Chelsea’s 4-4-2. However this can be easily be neutered by a 4-3-3 (which is essentially a 4-5-1) with a midfield trio of three of Lampard, Essien, Ramires or Mikel.

If I were Ancelotti I would consider the following line-up: Cech, Bosingwa, Ivanovic, Terry, Cole, Ramires, Essien, Lampard, Zhirkov, Torres, Anelka.

This would effectively be a 4-4-2, but it gives us the tactical flexibility to switch to a 4-3-3 if need be, with Anelka dropping wide right and Torres in the lone striker.

As aforementioned Drogba could then be a terrific impact striker, and the switch to a 4-4-2 may not be as deadly, if Essien, Lampard and Ramires have established a strong foothold on the middle of the park.

ROONEY
Everyone knows the story of Wild Wayne against West Ham. Containing Rooney is a key part of the clash. Ferguson’s recent tendency has been to place a partner with him to help him get back into match rhythm – but this “mission” has been somewhat fulfilled by a hat trick on the weekend.

So a 4-5-1 is highly feasible. Rooney likes to drop in deep and create space for pacier players to exploit, like Nani. This makes the United formation the conservative 4-6-0 which won the 2008 Champions League. To counter this, a defensive midfielder may be needed – but we’ve gone through all of this. 4-3-3 makes it another 1v1 encounter which Chelsea has already shown they can win. Essien’s mobility can help dictate a high tempo game similar to the one West Ham to reasonable success played for the first half on Saturday. Football is all about space, as Johann Cryuff once said. Tonight will be all about exploiting it.