What season was played at Safeco Field, against the Boston Red Sox, with a decision of L?
CREATE TABLE "pitchers" (
  "season" text,
  "pitcher" text,
  "decision" text,
  "opponent" text,
  "location" text
);
SELECT "season" FROM "pitchers" WHERE "location"='safeco field' AND "decision"='l' AND "opponent"='boston red sox';