Warren began his career at
Charlton Athletic, and was given a professional contract in March 2011. After several loan spells away from the club, he was released at the end of the 2011–12 season and joined
Barnet, where he made his debut against
Birmingham City in the
Football League Cup on 14 August 2012. He joined
Hastings United on loan on 28 March 2013, making eight appearances, but was unable to save them from relegation from the
Isthmian Premier Division. On 21 September 2013, he joined
Canvey Island on loan for a month. Warren was released by the Bees at the end of the 2013–14 season, playing only five times in his two seasons at the club. Manager
Martin Allen said: "I am currently undecided on Freddie. He has done well in both games he has played but at 21 he needs to be playing regular football which I cannot guarantee him. He has a terrific attitude but is at a crossroads because of his age in terms of what direction he should go in". Warren signed for
Canvey Island permanently on 6 June 2014. He joined
East Thurrock United in November 2015. ==References==