Who was the runner-up for the mazda senior tournament players championship tournament when the margin of victory was 2 strokes?
CREATE TABLE "senior_pga_tour_wins_9" (
  "date" text,
  "tournament" text,
  "winning_score" text,
  "margin_of_victory" text,
  "runner_s_up" text
);
SELECT "runner_s_up" FROM "senior_pga_tour_wins_9" WHERE "margin_of_victory"='2 strokes' AND "tournament"='mazda senior tournament players championship';