Who became the champion for the 1984 Grand Prix where Marty Davis was the runner-up?
CREATE TABLE "table1_29295463_9" (
  "week_of" text,
  "tournament" text,
  "champion" text,
  "runner_up" text,
  "semifinalists" text,
  "quarterfinalists" text
);
SELECT "champion" FROM "table1_29295463_9" WHERE "runner_up"='Marty Davis';