Ekaterina Alexandrova's indoor prowess won out over her clay aversion on her Porsche Tennis Grand Prix debut, where she defeated Karolina Muchova 4-6, 6-2, 6-3 in the first round.

Coming into this week, Alexandrova's first-strike power game had won her 37 of her previous 45 matches indoors, dating back to October 2018. But her career record in clay WTA main draws was just 10-19, and the Russian had yet to beat a Top 30 opponent on the surface. But that changed in Stuttgart, where she struck 46 winners en route to a two-hour, 17-minute victory over the World No.22.

"It's clay, and every win on clay for me is special," said Alexandrova afterwards.

Muchova had not played since reaching her first Grand Slam semifinal at the Australian Open in February due to a left abdominal injury. But in the first set, the Czech showed she had not lost her touch, coming up with a series of dropshots and volleys as she came from 1-3 down to take it 6-4.

Alexandrova had landed just 49% of her first serves in the opening set, and raising this number to 65% in the second was key as the World No.34 turned the match around. She also played with more focus while ahead, with a titanic hold for 5-2 after eight deuces proving crucial.

"I felt like if I lost that game on my serve we were gonna be even again, and it would be hard to play on her serve," said Alexandrova. "I think I started quite well in the first set, but I lost some vision in my game. In the second set I tried to be more active and push her, going to the net."

Muchova needed to take a medical timeout before the decider, and on resumption her intensity had noticeably faded. Alexandrova again managed to maintain an early lead, surviving a spate of double faults and saving two break-back points to hold for 4-1. From there, she rolled to set up a second-round clash against No.8 seed Belinda Bencic.

Alexandrova halts Muchova comeback in Stuttgart opener: Highlights

2021 Stuttgart

Anett Kontaveit, the 2019 runner-up to Petra Kvitova, also progressed into round two with a 6-2, 6-3 defeat over German qualifier Julia Middendorf in one hour and 11 minutes.

The unranked Middendorf, 18, is one of two teenage qualifying wildcards to have successfully made the main draw this year. The junior World No.42 had scored wins over Jana Fett and Tamara Korpatsch to make her WTA main draw debut.

Like 17-year-old Nastasja Schunk against Belinda Bencic on Monday, Middendorf gave a good account of herself in her first match against a Top 100 opponent. She showed off some impressive power, striking 17 winners - two more than Kontaveit - and three aces.

However, despite the occasional lapse into cheap error, Kontaveit was able to focus when it mattered, saving all eight break points she faced to set up a second-round clash against No.3 seed Sofia Kenin.