HUA HIN, Thailand – Zheng Saisai was given a tough workout in her opening match of the GSB Thailand Open Presented by E@ before she ultimately staved off the challenge of Natalija Kostic, 7-6(6), 6-0.

The No.4 seed required 72 minutes to claim the opening set against the WTA Tour main draw debutante, but once ahead steamed through the second with the loss of a game to seal the match in one hour 50 minutes.

Her serve was especially efficient, with 70% of first deliveries finding their mark, with 71% of those points won. Nevertheless, Kostic made her work hard for the win.

“She played really well. She’s a fighter. She had a lot of variety and always made me play extra shots. So I was slow into the match. I had to gradually find my way,” she said.

“She's got a style so you don't feel a rhythm on the court - she slices a shot then she lobs a shot - so I didn't feel the ball that well but I started to feel the ball and I started to turn it around.”

A quarterfinalist in Hua Hin last year, Zheng trailed by a break for the majority of the first against an opponent who settled impressively after being broken in the opening game due to a couple of double faults she delivered in succession.

It was a blow that the 25-year-old Serb recovered from quickly as she broke back en route to winning four successive games.

The slicing style of the WTA World No.183, who was a direct entry into the draw, initially upset Zheng but by the midpoint of the opening set she was beginning to get a foothold in the match.

Kostic maintained her strong level to win a big battle while serving at 4-2, but she was unable to do likewise when she had the balls in hand seeking the set. Having fallen 15-40 down, she crunched two winners but a third break point was too much to resist, with Zheng flicking over a drop that left her opponent floundering.

Back on terms, the set was pushed towards a tiebreak, in which Zheng opened up a 6-3 advantage, once again using a dropshot to devastating effect. Kostic’s fighting spirit was evident as she saved the trio of set points, though the set escaped her when she hit a backhand crosscourt narrowly wide.

Once ahead, Zheng showed the class that had seen her win 15 of her previous 18 matches against players outside the Top 100. Her array of shots were superior and more consistent than that of her opponent, and she wasted little time ploughing through the second set.

The Chinese, one of 10 players from her country in the draw, pounced as he opponent’s first-serve dropped to 21%, and lost only 11 points as she sealed the match with a bagel.

Next up for the 26-year-old is a meeting with either Wang Xinyu or Liang En Shuo.

2020 Hua Hin highlights: Zheng fights past Kostic