2018 BNP Paribas WTA FINALS,Singapore Karolina Pliskova (CZE) defeated Petra Kvitova (CZE) 63 645 and advances to the semifinals. Photo © Ray Giubilo

2018 BNP Paribas WTA FINALS,Singapore Karolina Pliskova (CZE) defeated Petra Kvitova (CZE) 63 645 and advances to the semifinals. Photo © Ray Giubilo

2018 BNP Paribas WTA FINALS,Singapore Singles final. Elina Svitolina (UKR) defeated Sloane Stephens (USA) 36 62 62 Photo © Ray Giubilo

2018 BNP Paribas WTA FINALS,Singapore Karolina Pliskova (CZE) defeated Caroline Wozniacki (DEN) 62 64 Photo © Ray Giubilo

2018 Nitto ATP FINALS FINAL Alexander Zverev (GER) defeated Novak Djokovic (SRB) 64 63 Photo © Ray Giubilo This image may not be reproduced or sold to third parties.

2018 Nitto ATP FINALS FINAL Alexander Zverev (GER) defeated Novak Djokovic (SRB) 64 63 Photo © Ray Giubilo This image may not be reproduced or sold to third parties.

2018 Nitto ATP FINALS FINAL Alexander Zverev (GER) defeated Novak Djokovic (SRB) 64 63 Photo © Ray Giubilo This image may not be reproduced or sold to third parties.

2018 Nitto ATP FINALS FINAL Alexander Zverev (GER) defeated Novak Djokovic (SRB) 64 63 Photo © Ray Giubilo This image may not be reproduced or sold to third parties.

2018 Nitto ATP FINALS Novak Djokovic (SRB) defeated Alexander Zverev (GER) 64 61 Photo © Ray Giubilo This image may not be reproduced or sold to third parties.