Madison Keys has added Maria Sharapova's former hitting partner, Dieter Kindlmann, to her team.

Kindlmann will join Lindsay Davenport, who works with Keys at the bigger events.

"I definitely needed someone who was to be there 100 percent of the time," Keys said in Madrid. "I've known him for a couple of years, not super well, but I always really liked him. After the first or second practice we had a really good feeling for each other."

The 22-year-old American has tried out several coaches during the past couple of years, rehiring Davenport even though the TV commentator and mother of four could not commit to a full coaching schedule.

Keys reached the Top 10 in 2016, but her 2017 season has been set back by left wrist surgery. She fell in her opening round in Madrid to Misaki Doi.

"It's going to take a while," Keys said of her return to top form.