Who is the partner with a score of 6–1, 6–4?
CREATE TABLE "doubles_19_10_9" (
  "outcome" text,
  "date" text,
  "tournament" text,
  "surface" text,
  "partner" text,
  "opponents" text,
  "score" text
);
SELECT "partner" FROM "doubles_19_10_9" WHERE "score"='6–1, 6–4';