CREATE TABLE table_21721351_18 (player VARCHAR, college_junior_club_team VARCHAR)

Which player belongs to deerfield academy (Massachusetts) college/junior/club team?
SELECT player FROM table_21721351_18 WHERE college_junior_club_team = "Deerfield Academy (Massachusetts)"
SELECT "player" FROM "table_21721351_18" WHERE "Deerfield Academy (Massachusetts)" = "college_junior_club_team"