ZHUHAI, China - No.5 seed Petra Martic sealed the final round-robin victory in the Orchid Group at the Hengqin Life WTA Elite Trophy, but by winning at least seven games in a 6-4, 6-3 defeat, Zheng Saisai nonetheless qualifies for the semifinals. 

Martic seemed on the precipice of qualifications herself as she built a 6-4, 4-2, 15-40 lead in the match, which would've allowed her an opportunity to serve for the match, and seal victory by losing the six games or fewer which she needed to advance.

However, Zheng sealed a crucial hold of serve that sealed her place in the final four with some clutch tennis, even though the Croatian capped her week in Zhuhai with the match victory.

"This is the first time I have this experience. Actually, I knew if I win a set, I for sure would be in, but I don't know exactly how many games," Zheng revealed to reporters after the match.

"I was pretty tight because I knew I don't need to win the match, so I was like scared a little bit. It's really the first time the feeling how I played -- very nervous."

After losing serve in the first game of the match, Zheng rallied to even the opener at 4-4 by taking back-to-back games, helping her cause towards reaching the magic number.

"After it got 4-4 [in the first set], I knew if I win one more game then I, it is my serve, so I have big chance to qualify, so I start to be so tight and I think I missed like three easy mistakes," she continued.

"I was a little mad because I couldn't stop thinking about this, it's just like really, it's a normal match, it's not a normal match, you know, I want to play...but I was a little bit over thinking.

"And the second set, I'm not sure how many games actually, I'm not sure, I was just playing how I can do. It doesn't matter like how many games I can win, just going to play. I was happy though."

The Chinese wildcard joins top seed Kiki Bertens and No.11 seed Karolina Muchova in the semifinals, with the winner of Friday's evening match between Elise Mertens and Aryna Sabalenka set to determine the last semifinalist.

In her second appearance in singles Zhuhai, Zheng advances out of the round robin stage for the first time, having gone 0-2 in the round robin in her first appearance four years ago.

"It's been a fantastic journey for me. Four years ago I just started my WTA journey and it's on a rising path," Zheng told Chinese reporters through a translator. 

"I learned a lot by playing with Venus Williams and Madison Keys [in 2015] and I learned how to play with those powerful players, because I know I knew I have a lot of weaknesses at the time and there are many things for me to learn.

"For the past few years there are ups and downs, I experienced some injuries, and this time I did pretty well, the first match is a solid win and today I also kind of passed the test. So it's been an acknowledgment of my effort for the past four years.

"Nothing happens overnight, I believe in making progress step by step, believing in solid training and try to build up my abilities bit by bit and to eventually overcome all the challenges. I'm very happy today."