Three-time Grand Slam champion Angelique Kerber added to her dismal run as she lost in three sets to lower-ranked Alison Riske at the Zhengzhou Open in China on Tuesday.

The 31-year-old German suffered premature exits at the US Open, French Open and Wimbledon in recent months, and split with her coach.

The former world No 1 is stuck in a deep rut and racked up another early loss at the hands of America’s world number 34. In an evening epic, Riske outlasted Kerber, ranked 15th, 5-7, 6-4, 7-6 (8/6) to move into the second round in Zhengzhou. The American had reached the quarter-final run at Wimbledon.

It was nothing short of a battle, that’s for sure,” Riske told after the match. “I knew going into it that it was going to be really tough, just because Angie is obviously an amazing player.

“And yeah, especially for a first round, it’s just really challenging. I’m just really proud of the way I fought through it. I tried to stay present as much as I could.”

Riske will next take on China’s Zheng Saisai, who beat Bibiane Schoofs in straight sets, 7-6(4), 6-1 earlier in the day to advance.

With AFP Inputs