Dee ihe na-aga n'ihu maka paragraf a - Mgbe afọ abụọ nke asọmpi kpụ ọkụ n'ọnụ na mwakpo ndị ọkpụkpọ, National na American League mere udo na, dịka akụkụ nke nkwekọrịta ahụ, ọtụtụ ndị otu egwuregwu kwadoro maka egwuregwu ngosi nke interleague mgbe oge 1903 gasịrị. A haziri usoro ndị a site na klọb ndị sonyere, dịka egwuregwu World Series nke 1880s. Otu n'ime ha jikọtara ndị mmeri abụọ ahụ, Pittsburgh Pirates nke NL na Boston Americans (nke e mechara mara dị ka Red Sox) nke AL; nke a maara dị ka 1903 World Series
egwuri na Huntington Avenue Grounds. Ọ bụ ndị nwe ụlọ abụọ ahụ mere ndokwa nke ọma tupu oge eruo, ebe ọ bụ na ndị otu abụọ ahụ bụ ndị isi nke otu egwuregwu site na oke oke. Boston meriri Pittsburgh site na egwuregwu ise ruo atọ, na-emeri site na itinye omimi n'azụ Cy Young na Bill Dinneen na nkwado nke ndị Royal Rooters. Egwuregwu ahụ wetara ọtụtụ mpako obodo na Boston ma gosipụta na Njikọ Njikọ Ọhụrụ nke America nwere ike imeri ndị mba.