Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_83 (surface VARCHAR, opponent VARCHAR)
### Question:
What was the surface of the match against bethanie mattek-sands?
### Answer:
SELECT surface FROM table_name_83 WHERE opponent = "bethanie mattek-sands"