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_2151643_3 (opponents VARCHAR, outcome VARCHAR, surface VARCHAR)
### Question:
Who were the opponents that led to an outcome of winner on a grass surface?
### Answer:
SELECT opponents FROM table_2151643_3 WHERE outcome = "Winner" AND surface = "Grass"