Last summer the premier league put into effect a new set of roster regulations, which can be found explained here. Premier league teams are now required to register 25 players at the close of both transfer windows (8/31 and 1/31). Any games played in the months of August and January are exempt from the roster restrictions, as those games are being played during an open window. Currently, Chelsea have only 19 players registered to the squad. The roster we named at the end of August can be found here. That leaves us with four available spots for homegrown players, and two for players developed abroad. A third "abroad" spot could be created by leaving Benayoun off of the squad in January if it doesn't look like he'll contribute in the second half.

There are several ways players can be classified that will be important to us. First, we have the under 21 player, of which we can have an unlimited amount:

an Under 21 player is defined as one who is under the age of 21 on 1st January in the year in which the season commences. For the 2010/11 campaign Under 21 players will have been born on or after 1st January 1989.

Players such as Simon Kjaer, who we've been linked to, would count as under 21 for the remainder of this season even though he is already 21 years of age. A homegrown player has been defined as follows:

A home grown player is defined as one who, irrespective of his nationality or age, has been registered with any club affiliated to the Football Association or the Welsh Football Association for a period, continuous or not, of three entire seasons or 36 months prior to his 21st birthday (or the end of the season during which he turns 21).

Currently we have 4 homegrown players: Ashley Cole, John Terry, Ross Turnbull, and Frank Lampard. Daniel Sturridge is under 21 this season, but will take a homegrown place next year. Michael Mancienne is on loan, but assuming he's not sold he will also be a homegrown player next year. None of our other young players will need to be named to the roster for a few years, so we do have some open spots going forward. Any players we sign from abroad who were born after 1/1/92 will eventually be classified as "homegrown", assuming they remain under contract with a team in England or Wales for three years.

One other rule that may come into effect involves goalkeepers. We've been linked to several goalkeepers, although I'm not sure how much stock I'd put into that. This tidbit could prove to be very interesting:

they will only be able to make alterations outside the windows if there are exceptional circumstances and the changes are approved by the Premier League board. For example, if a club has two out of three goalkeepers injured they may be permitted to bring in a replacement under the guidelines drawn up by a specially formed working party.

Should we sign a keeper, we could theoretically keep Hilario or Turnbull off the 25 man squad and still have them added if needed. In all likelihood it won't happen, but it would be far more likely to be Hilario's non-homegrown place that needed to be freed up if we do sign another keeper.

We are also still involved in the UEFA Champions League, which after a very favorable draw will likely see us with at least 4 more fixtures and possibly as many as 7. We'll hear the phrase "cup tied" tossed around quite a bit in the next six weeks. A cup tied player can be defined as follows:

In virtually all domestic and international club cup competitions, any player who makes an appearance for a club at any stage of the competition is "tied" to that club for all future matches during that season in the same competition.

This rule applies to both UEFA competition and the FA cup. Any player we sign that has participated in the FA cup to date will not be eligible to play for Chelsea. UEFA has relaxed the rule some for this season, allowing a single player who's club was eliminated prior to the end of the summer window to be added and allowed to participate, meaning we could add a player off of a team that failed to get out of the qualifying rounds. Any player who has participated in the group stages (Luis Suarez for example) will not be eligible to take part in any of the remaining fixtures this year.

Chelsea were confident to start the season with very little established depth in the squad. As the first half of the season has played out, that move has begun to look more and more questionable. Injuries and Malaria have struck, and the youth have been forced to play a more regular role than anticipated. It's been nice to see kids like Josh McEachran and Patrick Van Aanholt get their opportunity to shine (and those two have), but some of the kids who've been inserted haven't looked ready for the first team. Our current position in the table likely reflects the lack of depth.

Chelsea have will likely continue to be linked to transfers in several areas, most notably a young striker, right back, and central defense. A big positive in the way the squad was constructed is that unlike most "big" squads, we won't have to make any subtractions in order to add several players in January. We also likely won't have to sell any parts this summer to make way for new players. Hopefully this brief summary will lend some clarity to how additions would fit into the squad, both now and moving forward.