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The 1975 US Open was a tennis tournament that took place on the outdoor clay courts at the West Side Tennis Club in Forest Hills, Queens, in New York City, United States. The tournament ran from 27 August until 7 September. It was the 95th staging of the US Open, and the fourth Grand Slam tennis event of 1975. During the final three years at the Forest Hills location, 1975-1977, the US Open was played on a green-colored Har-Tru clay surface, a surface slightly harder and faster than red clay. The switch came after player complaints about the poor state and uneven ball bounce on the grass courts in Forest Hills. The tie-break scoring system changed in this championship. Previously a sudden death point was played at 4–4 with the winner the first to 5 points. It changed to the 13 point tie-break first to 7 points or the first player to win by two clear points if the scores reached 6–6.
Manuel Orantes
Chris Evert
Ilie Năstase
Margaret Court / 
Virginia Wade
Tom Okker / 
Chris Lewis, 6–4, 6–3
Natasha Chmyreva defeated 
Greer Stevens, 6–7, 6–2, 6–2