Dee ihe ndị ọzọ dị na paragraf a - Mgbe mba ya bụ́ Gris nabatara asọmpi Olimpik nke oge okpomọkụ nke 2004 n'Atens, Matsa mere asọmpi Olimpik mbụ ya mgbe ọ dị afọ 17, na-asọ mpi n'asọmpi igwu mmiri abụọ. O depụtara ụkpụrụ FINA B nke 25.61 (50 m freestyle) site na ihe omume nnwale Olympic na Athens Olympic Aquatic Center. N'ụbọchị mbụ nke egwuregwu ahụ, Matsa sooro Nery Mantey Niangkouara, Eleni Kosti, na Zoi Dimoschaki n'ọsọ 4 × 100 m freestyle relay. Ọ bụ ya ka a ga-ata ụta maka mbido ọpụpụ nke mbụ, mgbe a chụpụrụ ndị Gris n'asọmpi ahụ. Ihe fọrọ nke nta ka ọ bụrụ otu izu ka e mesịrị, na 50 m freestyle
, Matsa gbara onye nke iri atọ na atọ n'asọmpi ụtụtụ. Na-egwu mmiri na okpomọkụ asaa, ọ gafere Trinidad na Tobago's Sharntelle McLean iji bulie ebe nke asaa site na nkeji iri anọ nke abụọ (0.40) na 26.46.