Who was the opponent in the championship in Johannesburg, South Africa?
CREATE TABLE "career_finals" (
  "outcome" text,
  "date" text,
  "championship" text,
  "opponent_in_the_final" text,
  "score_in_the_final" text
);
SELECT "opponent_in_the_final" FROM "career_finals" WHERE "championship"='johannesburg, south africa';