Dee ihe ga-aga n'ihu maka paragraf a - bụ onye na-egwu mmiri Japan. Ọ gbara asọmpi n'asọmpi ụmụnwaanyị na-agba n'ụkwụ n'ụkwụ mita 200
ihe omume na 2016 Summer Olympics. N'ọnwa Eprel 2017, Hasegawa mebiri ndekọ ụwa nke ndị na-eto eto na 200 butterfly na 2:06.29 na Japanese Nationals. Ọ tozuru oke ịnọchite anya Japan na 2020 Summer Olympics.