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_50 (year INTEGER, event VARCHAR, opponent VARCHAR)
### Question:
what's the earliest year that the wimbledon opponent was zheng jie?
### Answer:
SELECT MIN(year) FROM table_name_50 WHERE event = "wimbledon" AND opponent = "zheng jie"