CREATE TABLE table_8450 ("Outcome" CLOB, "Date" FLOAT, "Tournament" CLOB, "Surface" CLOB, "Partner" CLOB, "Opponents" CLOB, "Score" CLOB)

Who did he play on a hard surface?
SELECT "Opponents" FROM table_8450 WHERE "Surface" = 'hard'
SELECT "Opponents" FROM "table_8450" WHERE "Surface" = 'hard'