Premise: Jeanne Evert Dubin (born October 5, 1957) is an American former professional tennis player and the younger sister of Chris Evert. She was ranked as high as 42nd by the WTA in 1975 and ninth within the United States alone in 1974. She reached the third round of the U.S. Open in 1973 and 1978. She won all 4 of her Fed Cup matches for the U.S. in 1974.
Hypothesis: Jeanne Evert won the US Open in 1973