What was the name of the tournament that the final was played against Yi Jingqian?
CREATE TABLE "singles_wins_6" (
  "date" text,
  "tournament" text,
  "surface" text,
  "opponent_in_the_final" text,
  "score" text
);
SELECT "tournament" FROM "singles_wins_6" WHERE "opponent_in_the_final"='yi jingqian';