Just a few seasons ago, Chelsea could reasonably lay claim to having one of the strongest central midfields on the planet. Michael Essien was at his swashbuckling best. Frank Lampard was, I'm reasonably informed, so soul-destroying to fans of other teams that the Catholic Church re-classified him as a demon, and the club had unprecedented depth on top of that.
Now, not so much. Michael Essien's knee is borked again, Frank Lampard looks as though age (and a major groin injury) are catching up to him*, and there are questions about more or less everyone else except Ramires. One of the strangest aspects of Chelsea's current midfield is that the available players is that it seems to imply a 2-1 shape rather than a 1-2: There are only two (and a half, if we're going to count Ramires) midfielders who should be playing high up the pitch: Lampard and Benayoun.
*See if you can generate the mental image of a groin injury chasing someone. It's pretty amusing.
Anyway, let's take a look at the players.John Obi Mikel has, for the past few years, been one of Chelsea's most important players. Nobody else in the squad has actually been able to play the lone holder role competently, so Mikel was the key to the Blues being able to use a 4-1-2-3. There seems to be a dedicated culture of Mikel haters countered by Mikel fanatics, and I'd have to say he's somewhere in the middle. He's clearly good enough to play for Chelsea, but his raw statistics overrate his passing ability, and he's inconsistent enough that he's occasionally a liability. And that's ok.
A newcomer may well push Mikel hard for his spot, however, Oriol Romeu is a La Masia product, and therefore he has ridiculous passing ability. Seriously, would anybody be surprised if Barcelona's academy sat on a deposit of radioactive mutagenic ore that gave them god-like vision on a football field? Or if a swathe of youngsters claimed they were molested by the wandering ghost of Johan Cruyff*? Anyway, Romeu is a solid defensive midfielder who can pass. Just how solid he is will determine how fast the 20-year-old gets into the Chelsea first team.
*He's not dead, but since nobody knows how that is he can still be a ghost.
Speaking of youngsters, Josh McEachran is ready for a real run-out in the Premier League. No, he's probably not going to be Jack Wilshere this season - he just doesn't have enough playing time for us to imagine he's at the same stage of development as the England international was last season. But regardless, he's still a very interesting option as a deepish playmaker. His passing range and vision is second to nobody on the roster (Cruyff got another one!), and his continued improvement in tackling and ball retention rather imply that he's going to turn into quite a player for Chelsea, and before too long.
Michael Essien's knee is all kinds of messed up, but he might make a return in 2012. In the meantime, the only true box-to-box player Andre Villas-Boas has at his disposal is Brazilian Ramires, who made a rather inauspicious (read: absolutely abysmal) start to his Chelsea career before turning things around later in the season and turning into a real asset. Ramires will probably remain quite good at everything, although we'd like to see more attacking out of him this year. That goal he scored against Manchester City to cap a 2-0 win was something quite special.
And now we come to Frank Lampard. At this point, it's difficult to understand why Chelsea seem to be so reliant on him, because he's getting to the point where he's really starting to slow down. He can still finish moves and strike from range, but when one builds a team around a player and said player goes into decline, bad things start to happen. Hence last year, I guess. Anyway, there's an argument to be made that Lampard needs to focus more on the pssing and less on the scoring with Fernando Torres around, and a lot of Chelsea's success will be based on how well they can get Lampard to adapt to a changing environment.
Last but not least is Yossi Benayoun, whose involvement last season following a transfer from Liverpool was somewhat curtailed by an Achilles injury sustained very early on. He's been very effective in preseason and is the closest thing we have to a true trequartista (thanks, PSG >:( ) so I'd look for him to be a fairly valuable member of the squad this year. Whether or not that's a good thing... well, you be the judge.