CREATE TABLE table_50584 ("Round" FLOAT, "Pick" FLOAT, "Overall" FLOAT, "Name" TEXT, "Position" TEXT, "College" TEXT)

During round 8 when the Position being picked was rb, what was the highest overall pick?
SELECT MAX("Overall") FROM table_50584 WHERE "Position" = 'rb' AND "Round" = '8'
SELECT MAX("Overall") FROM "table_50584" WHERE "Position" = 'rb' AND "Round" = '8'