CREATE TABLE table_name_53 (away_team VARCHAR, tie_no VARCHAR, home_team VARCHAR)

Who was the away team that played Northampton Town at home with a tie number of replay?
SELECT away_team FROM table_name_53 WHERE tie_no = "replay" AND home_team = "northampton town"
SELECT "away_team" FROM "table_name_53" WHERE "home_team" = "northampton town" AND "replay" = "tie_no"