Of the 333 key players (those with 10+ league starts) - 48 will be aged 32 or over by 31 August 2008, 140 between 27 & 31, 119 between 22 & 26 and 26 aged 21 or under.
A list of the 26 players under the age of 21 who made 10 or more appearances:
Aaron Lennon 2003-04 M England Tottenham Hotspur 2007-08 Cameron Jerome 2003-04 F England Birmingham City 2007-08 Cesc Fabregas 2003-04 M Spain Arsenal 2007-08 Craig Gardner 2003-04 M England Aston Villa 2007-08 Danny Guthrie 2003-04 M England Bolton Wanderers 2007-08 David Wheater 2003-04 D England Middlesbrough 2007-08 Gabriel Agbonlahor 2003-04 F England Aston Villa 2007-08 Gelson Fernandes 2003-04 M Switzerland Manchester City 2007-08 Joe Hart 2003-04 G England Manchester City 2007-08 Johan Djourou 2003-04 D Switzerland Birmingham City 2007-08 Lucas Leiva 2003-04 M Brazil Liverpool 2007-08 Mark Noble 2003-04 M England West Ham United 2007-08 Mikel John Obi 2003-04 M Nigeria Chelsea 2007-08 Nani 2003-04 M Portugal Manchester United 2007-08 Nedum Onuoha 2003-04 D England Manchester City 2007-08 Ryan Babel 2003-04 F Netherlands Liverpool 2007-08 Tom Huddlestone 2003-04 D England Tottenham Hotspur 2007-08 Anderson 2004-05 M Brazil Manchester United 2007-08 Fabrice Muamba 2004-05 M England Birmingham City 2007-08 Giles Barnes 2004-05 F England Derby County 2007-08 Jonny Evans 2004-05 D Northern Ireland Sunderland 2007-08 Lee Cattermole 2004-05 M England Middlesbrough 2007-08 Micah Richards 2004-05 D England Manchester City 2007-08 Michael Johnson 2004-05 M England Manchester City 2007-08 Victor Anichebe 2004-05 F Nigeria Everton 2007-08 Theo Walcott 2005-06 F England Arsenal 2007-08
The first year shown relates to their first year as a full time footballer. So for example Theo Walcott is the only 19 year old on the list - being born on 16/03/89 and hence turning 17 between 1 September 2005 & 31 August 2006.