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_21 (tackles VARCHAR, yards VARCHAR, fumr VARCHAR, totaltk VARCHAR)

### Question ###
what is the total number of tackles when fumr is 0, totaltk is 54 and yards is less than 0?

### Accurate SQL ###

SELECT COUNT(tackles) FROM table_name_21 WHERE fumr = 0 AND totaltk = 54 AND yards < 0