Crocker grew up in the small village of Sutton Poyntz near Weymouth in Dorset and attended Broadway Secondary School.
Although being given occasional live Premier League matches between 2005 and 2006, Crocker was clearly behind the Sky "Big Four" of Martin Tyler, Rob Hawthorne, Alan Parry and Ian Darke in the commentating pecking order.
As a result, Crocker left Sky to progress his career with Setanta Sports, working for them during the following three years.
In September 2010, it was announced that Ian Darke was leaving Sky Sports to join ESPN America as their leading football commentator.
Crocker was subsequently re-signed by Sky Sports on a permanent basis as an integral part of their football commentating line-up.