MASON, Ohio (AP) – A right forearm injury forced Swiss teen Belinda Bencic to withdraw from the Western & Southern Open after she dropped the first set against seventh-seeded Lucie Safarova 6-2 in the round of 16 on Thursday.
The 12th-seeded Bencic said she didn’t think the injury was very serious, but it was too soon to know if she could play in next week’s tournament at New Haven, Connecticut.
“I wasn’t 100 percent, and to beat Lucie or even compete against her, you have to be 100 percent,” she said. “I didn’t want to retire. This was the first I’ve ever had to retire. I hope it gets better.”
The forearm had bothered the 18-year-old for a while, she said.
“Every match, it was getting tighter and tighter,” she said. “I was hoping that a lot of (therapy) would help, but I couldn’t do it.”
Bencic was coming off the biggest moment of her brief career, when she won the title in Toronto and upset top-ranked Serena Williams in the semifinals last week.
Safarova will meet either 14th-seeded Elina Svitolina or unseeded Caroline Garcia in the quarterfinals at Cincinnati.
In men’s action, Ivo Karlovic double-faulted on match point, and fifth-seeded Stan Wawrinka pulled out a grueling 6-7 (2), 7-6 (5), 7-6 (5) win.
Karlovic’s second serve on match point hit the top of the net and landed out for his seventh double-fault of the 2-hour, 37-minute match.
Wawrinka, the reigning French Open champion, had to overcome 35 aces by Karlovic to reach the quarterfinals for the second straight year. Wawrinka finished with eight aces.
Also, qualifier Alexandr Dolgopolov reached the quarterfinals with a 6-3, 3-6, 6-4 win over Jerzy Janowicz. Dolgopolov had never made it past the first round in four previous Cincinnati appearances.