Diop was born in Paris, France. He played in the Ukraine for FC Metalurh Donetsk, spent the 2006–07 season on loan to FC Stal Alchevsk and Belgian side K.F.C. Germinal Beerschot. In August 2008 he moved to Cyprus and Apollon Limassol before playing on loan for PAEEK FC. He then played for Spanish side SE Eivissa-Ibiza. On 22 October 2009, Diop was one of four new players brought to Darlington by new manager Steve Staunton. Diop was signed on a short term contract, although he needed international clearance to officially complete his signing and picked up a slight muscle injury ruling him out of that weekend’s league trip to Barnet. He scored his first goal for Darlington in a 3-1 FA Cup defeat at Barnet on 7 November 2009. He was one of several players released early from their Darlington contracts towards the end of the 2009–10 season.
On 29 October 2015, Diop signed for Bedford Town FC, teaming up with former Hereford United manager Jon Taylor.
He signed for Rushall Olympic F.C. in 2016.