MILAN, ITALY - NOVEMBER 10: Andrey Rublev of Russia looks on in his match against Borna Coric of Croatia during the semi finals on day 4 of the Next Gen ATP Finals on November 10, 2017 in Milan, Italy. (Photo by Emilio Andreoli/Getty Images)
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MILAN, ITALY - NOVEMBER 10: Andrey Rublev of Russia returns a forehand in his match against Borna Coric of Croatia during the semi finals on day 4 of the Next Gen ATP Finals on November 10, 2017 in Milan, Italy. (Photo by Emilio Andreoli/Getty Images)
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MILAN, ITALY - NOVEMBER 10: Borna Coric of Croatia reacts after missing a point in his match against Andrey Rublev of Russia during the semi finals on day 4 of the Next Gen ATP Finals on November 10, 2017 in Milan, Italy. (Photo by Emilio Andreoli/Getty Images)
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MILAN, ITALY - NOVEMBER 10: Borna Coric of Croatia returns a forehand in his match against Andrey Rublev of Russia during the semi finals on day 4 of the Next Gen ATP Finals on November 10, 2017 in Milan, Italy. (Photo by Emilio Andreoli/Getty Images)
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MILAN, ITALY - NOVEMBER 07: Andrey Rublev of Russia returns a forehand in his match against Gianluigi Quinzi of Italy during Day 1 of the Next Gen ATP Finals on November 7, 2017 in Milan, Italy. (Photo by Emilio Andreoli/Getty Images)
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