Who was the match against when on a clay surface during round 2r?
CREATE TABLE table_name_19 (
    against VARCHAR,
    round VARCHAR,
    surface VARCHAR
)
SELECT against FROM table_name_19 WHERE round = "2r" AND surface = "clay"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: Who was the match against when on a clay surface during round 2r? ### Input: CREATE TABLE table_name_19 (
    against VARCHAR,
    round VARCHAR,
    surface VARCHAR
) ### Response: SELECT against FROM table_name_19 WHERE round = "2r" AND surface = "clay"