Complex sentence: Whitfield was part of the Bradford City academy until the age of 16, upon his release from Bradford's youth system Whitfield joined the Silsden under-19 side, before signing for the Guiseley academy.
Split into simpler sentences: Whitfield was part of the Bradford City academy until the age of 16. Upon his release from Bradford's youth system Whitfield joined the Silsden under-19 side, before signing for the Guiseley academy.