Players Chelsea have brought in since 03/04: Paulo Ferreira, Arjen Robben, Peter Cech, Scott Parker, Neil Sullivan, Claude Makelele, Hernan Crespo, Alexei Smertin, Adrian Mutu, Joe Cole, Juan Veron, Wayne Bridge, Damien Duff, Geremi, Glen Johnson, Craig Roscastle, Yves Makaba-Makalambay, Jiri Jarosik, Ricardo Carvalho, Didier Drogba, Tiago, Mateja Kezman, John Obi Mikel, Ben Sahar, Andrei Shevchenko, Salomon Kalou, Michael Ballack, Michael Essien, Shaun Wright-Phillips, Lassana Diarra, Scott Sinclair, Asier Del Horno, Claudio Pizarro, Steve Sidwell, Ashley Cole, Khalid Boulahrouz, Henrique Hilario, Franco Di Santo, Branislav Ivanovic, Nicolas Anelka, Juliano Belletti, Florent Malouda, Deco, Carlos De Silva Mineiro, Quaresma, Jose Bosingwa, Daniel Sturridge, Ross Turnbull, Yuri Zhirkov, Nemanja Matic ||| Yossi Benayoun, Ramires, Fernando Torres, David Luiz, Matej Delac, Thibaut Courtois, Oriol Romeu, Romelu Lukaku, Ulises Davila Plasencia, Juan Mata, Raul Meireles, Gary Cahill, Kevin De Bruyne, Patrick Bamford, Lucas Piazon, Marko Marin, Eden Hazard, Thorgan Hazard, Oscar, Cesar Azpiicueta, Victor Moses, Demba Ba, Wallace, Andre Schurlle, Marco van Ginkel, Mark Schwarzer, Cristian Cuevas, Samuel Eto'o, Willian, Christan Atsu.
That's 80 players. The players in bold are players that were involved in 5 seasons or more at the club (The ||| marks when it becomes impossible for this to have happened yet). The players in italics are players that are still there. The underlined players played 100+ games. So if we say a 'core' or 'spine' is made up of the players who were there for 5 seasons and played 100 games, that gives Chelsea a spine consisting of:
Paulo Ferreira - Nope. Became a bit-part player after three years there.
Petr Cech - I'd agree he's been part of the spine.
Claude Makelele - An integral part of the team for a long enough length of time to be considered part of a 'spine' or 'core'.
Hernan Crespo - Nope. Spent more time away on loan than he did at the club.
Joe Cole - Agree with. Spent 7 years there, left when he wasn't good enough anymore.
Wayne Bridge - Nope. Managed over 30 games just twice, was just cover for Cole after a couple of seasons.
Ricardo Carvalho - I'd say he was a core member of the squad. A fixture in the defence for a good few years, arguably let go a season early.
Didier Drogba - Was definitely a key figure up until he left, which was mainly due to his ability to keep his performances at the level they needed.
John Obi Mikel - Certainly been around for a while but he's by no means a central figure in the team.
Salomon Kalou - As with Mikel, stayed around for a while but was never a central figure.
Michael Essien - A key player for a few seasons so I'd agree he was part of the team's spine. Not so much anymore.
Ashley Cole - Key player for a number of years.
Branislav Ivanovic - Not really a key player but he's been a pretty consistent figure in the defence for a few seasons now so he qualifies.
Nicolas Anelka - Only actually spent 4 1/2 years there but covered 5 seasons. Not really a key figure and only had 3 seasons where he played a great deal.
Florent Malouda - Over 30 games a season for 5 straight years so I reckon he qualifies as being part of a core.
So out of 80 signings, only 9 look remotely like they were part of any sort of core. Two of those are Malouda and Ivanovic so I'm not really sure if they count, and only Cech and Cole really play for them anymore. Essien's apparently still on the books but his days are numbered, and I don't think Mikel is ever going to be a key player for them. Looking at the players who haven't had enough time to qualify as key players with my parameters, the only one who actually looks like he might become part of one is David Luiz and there were rumours he was off in the summer. You could argue the case for Oscar as well. Mata looked a certainty until Mourinho came back and I wouldn't be surprised to see him leaving soon, Torres has been so hit and miss he'll never be part of one, and the rest just haven't been there long enough to judge properly. I think it's certainly fair to say that Chelsea have a bit of a revolving door policy when it comes to players as well as managers.
Not that this has anything to do with the fecking thread.