Gary started his career locally with the likes of Mangotsfield United and Team Bath, before joining Newport County in 2009 when the University side folded.

Warren captained Newport to the Conference South title in his first season in Wales. After three successful years with The Exiles,  Warren signed for Inverness Caledonian Thistle, managed by Terry Butcher.

Whilst North of the Border,, Warren enjoyed another successful spell as he again captained his new side in Scotland’s top flight and won domestic honours. Upon returning to England, Warren had spells at Yeovil Town, Torquay United and Tiverton Town. Now retired from playing, Warren has coached at the Ross County Academy in Scotland, before becoming Weston’s Academy Manager from January 2025, and first-team Interim Assistant Manager from October 2025.