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wta on Twitter: "25 Years Ago... 1988--> Steffi Graf won the #USOpen completing the 1st calendar-year Grand Slam since 1970! #tennis http://t.co/wyJPqk7HJD" / Twitter
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The US Open introduced the tiebreak set 50 years ago today - Official Site of the 2023 US Open Tennis Championships - A USTA Event
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