San Francisco Giants refused to play against the American League champion in 1904 .
`` It is sometimes called the Junior Circuit because it claimed Major League status for the 1901 season , 25 years after the formation of the National League ( the `` '' Senior Circuit '' '' ) .At the end of every season , the American League champion plays in the World Series against the National League champion ; two seasons did not end in playing a World Series ( 1904 , when the National League champion San Francisco Giants refused to play their AL counterpart , and 1994 , when a players ' strike prevented the Series ) . ''
American League