|Full name||Derek Thomas Allan|
|Date of birth||24 December 1974|
|Place of birth||Irvine, Scotland|
|Height||6 ft 0 in (1.83 m)|
|Current club||Greenock Morton (U17 coach)|
|1996||→ Brighton (loan)||8||(0)|
|1996–1999||Brighton & Hove Albion||67||(2)|
|2001–2004||Queen of the South||47||(0)|
|* Senior club appearances and goals counted for the domestic league only.
† Appearances (Goals).
He is currently the coach of Greenock Morton's U17 side.
Allan aka Swan, Swan Neck, Big Swan or "Christ look at the size of that fellas neck" was born in Irvine, Scotland and started his professional career at Ayr United, where he made only five appearances. After just one year at the club he was sold to Southampton of the English Premiership for a fee of £75,000 in March 1993.
Southampton's manager Ian Branfoot saw Allan as "one for the future" but a series of niggling groin strains restricted him to just eight minutes when he came on as a late substitute for Matthew Bound in a 1–0 defeat at Manchester City on 1 May 1993.
In March 1996 Jimmy Case took him on loan to Brighton, before making the move permanent. In the three years he spent at Brighton he made 67 league appearances, scoring twice. In 1999 Allan joined non-league side Kingstonian and was player of the season in the 1999–00 season. During his time at Kingstonian he took up part-time employment with a stationery supplier.
In 2001 he was signed by Scottish side Queen of the South. His stay was again hampered by injuries and he was limited to just 47 league appearances. Allan spent the last season of his career at Dumbarton, before early retirement at the age of just 30.
- Duncan Holley & Gary Chalk (2003). In That Number - A post-war chronicle of Southampton FC. Hagiology. pp. 227 & 472. ISBN 0-9534474-3-X.
- "Queen of the South Squad Details 2003/2004". www.qosfc.com. Archived from the original on 5 March 2007.
- "Morton's past, present and future under Hawke's eye". Scottish Football League. 9 December 2012. Retrieved 10 December 2012.