Chelsea and other Premier League clubs could be forced to alter their transfer policy in future as a result of a reported new proposal FIFA on limiting the number of players over the age of 21 a club can send out on loan at any one time to eight.

Chelsea currently have 40 players out on loan, including 27 who are over the age threshold and would therefore contravene any new rule that might be passed.

Chelsea v Newcastle United - The Emirates FA Cup Fourth Round

The Premier League club has engaged in a controversial tactic of 'stockpiling' talent in recent years, with many individuals brought in and loaned out. It results in some player being contracted at Stamford Bridge for years rarely, or even never, playing in a first team game.

Tomas Kalas, now 25 years of age, joined Chelsea in 2010. He has played four senior games for Chelsea, but has spent six of the last seven seasons on loan at Vitesse, Köln, Middlesbrough, Fulham, and now Bristol City, signing his most recent Chelsea contract just last year.

Croatian goalkeeper Matej Delac left Chelsea this summer, but before that he was bizarrely the club's longest serving player even though he had never made an appearance. In eight years as a Chelsea player, Delac had been loaned out as many as 10 times.

Tiemoue Bakayoko and Michy Batshuayi are two of the more high profile players currently out on loan, but with the likes of Baba Rahman, Kurt Zouma, Kenedy, Charly Musonda, Matt Miazga, Eduardo, Michael Hector, Jamal Blackman and others also still under contract and temporarily playing their football elsewhere, Chelsea may have to move players on in future.

Chelsea are not the only club who use the transfer market in such a way. Manchester City employ a similar policy on a smaller scale, often bringing in players from their partner clubs and loaning them out, like Mix Diskerud (pictured below), as well as Aaron Mooy in the past.

However, with only nine players over 21 currently out on loan, the Daily Mail notes that City are not actually worried about the new FIFA proposal as they could easily fall in line.

IFK Goteborg v IK Sirius FK - Allsvenskan

One place there might be considerable opposition is Italy, where loans are much more commonplace. Juventus, for example, have 40 players on loan at various clubs across Italy and the rest of Europe, with many over the age threshold.