2019 US Open – Day 2

NEW YORK, NEW YORK - AUGUST 27: A general view of the grounds on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Steven Ryan/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Stefanos Tsitsipas of Greece returns a shot against Andrey Rublev of Russia during their Men's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Mike Stobe/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Stefanos Tsitsipas of Greece returns a shot against Andrey Rublev of Russia during their Men's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Mike Stobe/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Naomi Osaka of Japan reacts against Anna Blinkova of Russia during their Women's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Elsa/Getty Images)

2019 US Open - Day 2

Naomi Osaka of Japan plays against Anna Blinkova of Russia during their Round One Women's Singles match at the 2019 US Open at the USTA Billie Jean King National Tennis Center in New York on August 27, 2019. (Credit: TIMOTHY A. CLARY/AFP/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Naomi Osaka of Japan looks on against Anna Blinkova of Russia during their Women's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Elsa/Getty Images)

2019 US Open - Day 2

Naomi Osaka of Japan shakes hands with Anna Blinkova of Russia after winning their Round 1 match, during the Round One Women's Singles match at the 2019 US Open at the USTA Billie Jean King National Tennis Center in New York on August 27, 2019. - Osaka won 6-4, 6-7 (5/7), 6-2. (Credit: TIMOTHY A. CLARY/AFP/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Cori Gauff of the United States returns a shot against Anastasia Potapova of Russia during their Women's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Clive Brunskill/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Cori Gauff of the United States celebrates after defeating Anastasia Potapova of Russia during their Women's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Clive Brunskill/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Cori Gauff of the United States celebrates after defeating Anastasia Potapova of Russia during their Women's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Clive Brunskill/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Rafael Nadal of Spain reacts against John Millman of Australia during their Men's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Mike Stobe/Getty Images)

2019 US Open - Day 2

NEW YORK, NEW YORK - AUGUST 27: Rafael Nadal of Spain looks celebrates victory after defeating John Millman of Australia during their Men's Singles first round match on day two of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2019 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Clive Brunskill/Getty Images)