GSTAAD, Switzerland - No.6 seed Carina Witthoeft booked a blockbuster quarterfinal with No.3 seed Anett Kontaveit after a come from behind victory over Rebecca Sramkova, outlasting the big-hitting Slovak, 2-6, 6-2, 6-2 at the Ladies Championship Gstaad.

"It wasn’t easy because the bounce is so high here, so it went from very low on the grass to very high!" Witthoeft said after the match. "We practiced a lot to adjust to the high balls, but it’s definitely different."

Witthoeft has been trending upward in 2017, getting back inside the Top 70 after reaching back-to-back third rounds at Roland Garros and Wimbledon. The German youngster had split her last two meeting against Sramkova last season, and was in for a long day at the office when she fell behind a set on Gstaad's Centre Court.

"She’s a tough player and it’s not easy to play against her. It was a tough match but I’m very happy to be through."

The No.6 seed rebounded in the next two sets, dropping just four points behind her first serve in the second and breaking serve six times overall to secure the win after one hour and 53 minutes on court.

Up next for Witthoeft is No.3 seed Anett Kontaveit, who needed that exact time to overcome Russian teenager Anna Kalinskaya earlier in the day. Kontaveit won their most recent encounter in straight sets at the Ricoh Open - en route to the Estonian's maiden WTA title - but their only clay court meeting did go the distance.

In the meantime, Witthoeft is enjoying the Gstaad scenery.

"It’s so nice here. Yesterday, we went to the mountains. Well, we drove, we didn’t climb!" she laughed. "It's  a lot of fun here."

Around the grounds, Sara Sorribes Tormo and Tamara Korpatsch joined Witthoeft and Kontaveit in the quarterfinals. Sorribes Tormo ousted former Mutua Madrid Open semifinalist Louisa Chirico, 6-1, 7-5, while Korpatsch recovered from a set down to defeat Greece's No.1 Maria Sakkari, 5-7, 6-3, 6-0.