CREATE TABLE table_name_51 (runner_s__up VARCHAR(255), margin_of_victory VARCHAR(255), tournament VARCHAR(255))
What is Runner(s)-Up, when Margin of Victory is 1 Stroke, and when Tournament is Joburg Open 1?
    
SQL: SELECT runner_s__up FROM table_name_51 WHERE margin_of_victory = "1 stroke" AND tournament = "joburg open 1"