STUTTGART, Germany - No.6 seed Kiki Bertens was made to work in her first match at the Porsche Tennis Grand Prix, but emerged victorious against German qualifier Anna-Lena Friedsam in two sets, 7-5, 6-2 to claim her first ever victory in Stuttgart. 

Already a known powerhouse on clay, last year Bertens proved to be an all-surface threat after a career-best season saw her lift trophies at Charleston, Cincinnati and Seoul. She also reached a second clay final at Madrid - her biggest final to date - and ended the clay season with a 15-5 record.

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But Bertens still had her work cut out for her against Friedsam, a German player who’d fought through three tough qualifying rounds who enjoyed vocal support from fans at the Porsche Arena.

“I’ve never won a match here, and I had a lot of break points that I didn’t take,” Bertens told press afterwards. “I was just really happy that I could finish it in two.

“I think she played a good match. She didn’t give any free points in the first set. So, I was just happy with the way I managed to play.”

Friedsam came out swinging, playing her aggressive game - but she quickly found herself under pressure from Bertens. The No.6 seed stepped into the returns, and was rewarded with five break point chances across two long Friedsam service games - three at 2-1 and two more at 4-3 - but the German held firm each time.

Bertens, who had only dropped three points in her first four service games, showed her mounting frustration as both players remained on serve. Finally, it was Bertens who broke through first, converting her seventh break chance to lead 6-5.

The drama ratcheted up again as Friedsam replied emphatically, earning her first two break chances against Bertens as she eagerly tried to send them into a tiebreaker, the Porsche Arena crowd willing her on. But finally it was Bertens who struck once again, dismissing both break chances and closing out the set after a tight 65-minute battle.

With the first set under her belt, Bertens raised her level heading into the second, firing winners off both wings and maintaining the aggression. She broke early to lead 2-1, and notched back-to-back love games to end the set with a second break at 5-2 to claim the match - and her career-first victory in Stuttgart.

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“You think it is clay you’re playing on but it’s not really,” Bertens explained. “It’s like really slippery. It’s tough to move here. I think normally I move pretty good on clay and I think that’s the same with Simona [Halep], but here you kind of not have that grip. When you’re standing you’re kind of sliding around so you never have like a really good grip.

“I think also that the really aggressive players, they play really well here. You see Pliskova last year she won the tournament. So, I think that’s the key here to play aggressive. That’s what I tried but I still need to improve a little bit.”

Up next, No.6 seed Bertens will take on the winner between Mandy Minella, another qualifier, and Dubai champion Belinda Bencic, ranked World No.20.