By Chris Oddo | Friday April 8, 2016

American Sloane Stephens battled through some exceptionally tough resistance from 18-year-old Russian Daria Kasatkina to book her place in the Volvo Car Open semifinals in Charleston for the first time on Friday.

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Stephens kept alive her bid for a third WTA title this season by saving a match point to notch a 6-1, 5-7, 7-5 victory over the World No. 35.

Kasatkina showed a lot of grit and perseverance to rebound from a shaky first set that saw her win just 6 of 19 points on serve and get broken on all three break points she faced.

Kasatkina was a different player down the stretch and nearly claimed what would have been a noteworthy victory. She broke back to get on serve in set three then saved two break points to hold for 5-4, but Stephens stood tall when the Russian held a match point with the American serving to stay alive in the final set. At the end of a long rally, Stephens pulled the trigger on a perfectly placed inside-out forehand winner and she did not look back from there.

"I was just fighting for every point,” said Stephens after winning the final 11 points of the match to close affairs in two hours and 24 minutes. “Obviously the conditions were really tough and I was playing a really good player. She's had some really good results, so I knew from the beginning that it was going to be a battle.”

Stephens advances to face top-seeded Angelique Kerber in one of Saturday’s semifinals, with 5th-seeded Sara Errani facing Elena Vesnina in the other.

Defending champion Kerber didn’t face a break point in taking down Irina-Camelia Begu of Romania. Kerber has never defended any of the eight titles she has won in her career.

2011 runner-up Elena Vesnina continued her fine form by edging Germany’s Laura Siegemund, 7-5, 6-4, while Errani battled through a complicated first set and finished strong to down Yulia Putintseva, 7-6(2), 6-1.