Dee ihe na-aga n'ihu maka paragraf a - N'egwuregwu Olympic nke 2004 n'oge ọkọchị na Atens, Lagoun ruru eru dị ka onye na-egwu mmiri n'otu n'otu maka ụmụ nwoke 100 m urukurubụba. O wepụtara oge ntinye FINA B nke 53.66 site na European Championships
na Madrid, Spen. Ọ gbara ndị ọzọ na-egwu mmiri asaa na okpomọkụ nke ise, gụnyere onye kachasị mma Milorad Čavić nke Serbia na Montenegro. Ọ gbara ọsọ gaa n'ọnọdụ nke ise site na 0.24 nke abụọ n'azụ onye France bụ Frédérick Bousquet na 53.87. Lagoun enweghị ike ịga n'ihu na ọkara ikpeazu, ebe ọ nọ na nke iri abụọ na isii n'ozuzu na preliminaries.