Defending champion Sabalenka beat during day of upsets in Shenzhen

SHENZHEN, China (AP) On a day of upsets at the Shenzhen Open, Kristyna Pliskova beat defending champion Aryna Sabalenka 6-4, 6-4 and Anna Blinkova defeated top-seeded Belinda Bencic 3-6, 6-3, 6-3 on Tuesday.

Pliskova had 15 aces and saved 11 break points against Sabalenka.

''She's playing so fast, so I had to be ready from the first point. My serve was there, which is always important, so I'm happy that I won,'' Pliskova said. ''I'm happy because I reached the quarterfinals here two years ago, so I'm happy to be back there and looking to see if I can do more.''

Pliskova will next play Kateryna Bondarenko after she defeated eighth-seeded Shuai Zhang 7-6 (8), 6-3 in the second round.

Blinkova rallied to beat Bencic in her opening-round match, serving a dozen aces and breaking her opponent's serve five times.

''It was a great performance from me today,'' Blinkova said. ''I prepared very carefully and I'm happy that I played good tennis. I was thinking to just fight for every point.''

The 21-year-old Blinkova lost five of the first six games but recovered well.

''I didn't feel great in the beginning of the match,'' Blinkova said. ''I didn't play bad, but I managed to increase the level of my game slowly, step by step.

''I said to myself that I needed to put more balls in the court, because I was giving her too many mistakes. I tried to play big margins, but aggressive.''

The Russian will next face Zarina Diyas in the second round. Diyas defeated wild-card entry Yingying Duan 6-3, 6-4.

Elise Mertens also reached the quarterfinals, beating Xiyu Wang 6-4, 6-3.