SHENZHEN, China - From Singapore to Shenzhen, Elina Svitolina will once again play for the title at the WTA's showpiece event.

The Ukrainian booked a spot in the final of the Shiseido WTA Finals Shenzhen at the close of Saturday's first semifinal when Belinda Bencic retired due to cramping in the deciding set.

As It Happened: Svitolina extends WTA Finals streak to 10 after outlasting Bencic

The No.8 seed and defending champion worked to turn the match around after losing the opening set as the Swiss' concerns grew, and ultimately, the pair shook hands with Svitolina leading 5-7, 6-3, 4-1. 

"It's tough to play someone who has been injured, been injured on the court," Svitolina said after the match. "It was tough for her.

"It's still kind of not realizing that I'm in the final. It's the very, very last match of the season.

"Definitely tomorrow, I'm going to leave everything on the court and fight just to try to get another trophy here."

The Swiss was ahead for much of the opener, as she broke in the sixth game to lead 4-2, but concerns first appeared when she received a medical timeout while leading 6-5, receiving treatment on her right hamstring. 

"I started cramping in my foot and again in my hamstring," Bencic said.

"I really didn't want to retire. I tried. Sometimes, I just tried to make a good serve, play no rallies. It just wasn't enough.

"I wanted to finish the match. It was not possible. I'm really disappointed about how my body failed me.

"It doesn't feel good that I just couldn't do more, but obviously credit to Elina. She made the rallies long. She did the right things. Obviously, she has a great advantage on these kind of courts, playing great at the WTA Finals."

Though Bencic won a thrilling game to break serve and seal the opener, she again received visits from the trainer over the course of the second and third sets.

The Ukrainian broke to start the second set, and never again trailed from that point.

"To stay into the match, it was tough. When someone injured, [she] tries to go for more," Svitolina said. "Actually, she was hitting the ball very good...I had to try to move her.

"This was not easy because it's tough to find a balance when you have to really hit the ball, then when you have to try to direct the ball well.

"She was going for it. Sometimes, of course, she was missing a lot. Sometimes she was hitting amazing shots. That's the challenge, what you have to be aware of."

She passed her biggest test later on in the middle set, as she saved a pair of break points which would've seen Bencic level at 3-3, and ultimately broke once more to send the match to a decider.

With momentum now firmly in her corner, Svitolina lost just four points across the first three games of the final set, and though Bencic battled valiantly to hold serve in the fourth game, she ultimately could not continue after Svitolina held once more, to love. 

The No.8 seed served a staggering 16 aces in the match, as she was never broken after the first set.

The Ukrainian fired off 37 winners to just 20 unforced over the course of one hour and 49 minutes, as Bencic racked up 29 in each category - with 15 of those winners coming in the first set. 

"Today was actually very good serving. At the beginning, I was serving really great," she added. "I think this is actually my record for one match, to serve 16 aces.

"It's something really positive. I hope I can keep it up for tomorrow's match, as well."

Svitolina arrived in Shenzhen as the only one of the elite eight to not reach a final in 2019, but is now one win, against either World No.1 Ashleigh Barty or World No.2 Karolina Pliskova, away from a double victory on Chinese soil.

"With Karolina, we played already this week. If I'm going to play her, it's going to be interesting match. I try to just stay focused," she said.

"It doesn't matter who I'm going to play, Ashleigh or Karolina, No. 1 and No. 2 in the world, so you have to be ready, you have to fight."

The Ukrainian not only has a chance to again raise the trophy at the tour's last tournament of the year, but also take home a record-breaking $4.725 million purse after finishing undefeated in round robin play.

"I have an important match tomorrow to win. For me, I try to take one match at a time. You don't have to think so much ahead, so much what's going on," she continued. 

"It's such a big tournament like this, when you straight have to play someone who is in the top eight, someone who presents straightaway the tough game and you have to be from the beginning very focused and ready, that's what we try to do.

"It's every match from the beginning you have to be on it, have to be focused, have to be presenting your best game, your best mental conditions, physical conditions.

"I always like to push my limits. That's what I try to do."