Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_93 (opponent VARCHAR, aces VARCHAR, event VARCHAR)

### Question ###
At the 2001 Davis Cup, what Opponent had less than 50 Aces?

### Accurate SQL ###

SELECT opponent FROM table_name_93 WHERE aces < 50 AND event = "2001 davis cup"