Richardson made his Leeds debut as a second-half substitute against Hapoel Tel Aviv during the 2002–03 UEFA Cup campaign. He made his full debut against Arsenal at right full-back, a position he was tipped to have on a permanent basis after the retirement of first team regular Gary Kelly. Richardson suffered Premiership relegation with Leeds in 2004. Since then, Richardson covered a variety of roles for Leeds. He spent two spells on loan at Stoke City in 2003, scoring once against West Ham.