Unseeded Zheng Jie recovered from a set down to beat Svetlana Kuznetsova in the semi-finals of the Auckland Classic on Friday and set up a showdown with Italy's Flavia Pennetta.

Fourth seed Pennetta, the form player of the tournament, waltzed into Saturday's final with a straightforward 6-1, 6-2 victory over Germany's Angelique Kerber.

World number 19 Kuznetsova was expected to join her, having dropped only one set in six previous clashes with Zheng, whose ranking has plummeted following wrist surgery.

Their semi-final initially went according to expectations, with Russia's Kuznetsova, seeded third, taking the first set 6-2.

But her form unravelled as the match progressed with Zheng fighting back to take the second set 6-3 and racing into a 5-1 lead in the third.

Kuznetsova broke Zheng, held her own serve and then reached break point at 3-5 before the Chinese world number 48 was able to finish off the match for a 2-6, 6-3, 6-3 victory.

"When I lost the first set my coach came onto the court and told me to focus on every point and then try to play well," Zheng said.

"This is the first tournament of the year and I wanted to go a long way in it and I'm very thankful that my coach came to support me," she said of her coach, who is also her husband.

While it took Zheng two hours 28 minutes to prevail over Kuznetsova, Pennetta needed just 59 minutes to put Kerber away and exact revenge for her quarter-final loss to the German at last year's US Open.

Pennetta admitted she was driven by the previous loss and was quick to cash in on Kerber's high error count.

"It was an emotional match for me. Last time I played against her I lost in the quarter-final of the US Open, so I had a lot of things on my mind," said Pennetta, a beaten finalist in Auckland in 2010.

"But I think I played really well today, I have to be proud of myself. I was fast on the court today. She was hitting the ball really hard but I was ready to play one more ball all of the time, so I'm really happy."