SINGAPORE -  Elina Svitolina beat world number one Simona Halep in straight sets to send her crashing out of the WTA Finals and hand breakout French star Caroline Garcia a place in the semis on Friday.

Svitolina, the world number four, was already eliminated after losing her first two matches but she took Halep down with her as she won 6-3, 6-4 in 71 minutes. Halep needed victory to keep her campaign alive but the Romanian struggled to click into gear against a relaxed Svitolina at the Singapore Indoor Stadium.

It means Garcia, the lowest-ranked player in the draw, tops Red Group and will play Venus Williams on Saturday, while Caroline Wozniacki will face Karolina Pliskova in the other semi-final. Svitolina went for her shots and dictated from the back of the court, rattling a shaky Halep, who had suffered a big loss to Wozniacki in her previous match. "I played free it was a good match for me and I am very happy to finish in Singapore with the win," the Ukrainian said.

Svitolina dictated from the start, breaking Halep's tentative serve straight away and winning the opening three games before claiming the first set in 31 minutes. Halep fought back in the second set with an early break but she was broken straight back and her head dropped when Svitolina claimed what turned out to be the decisive break in game seven. Even though she endured disappointment in Singapore, Halep will finish the year as world number one if Pliskova does not lift the trophy on Sunday.

Earlier Garcia, the world number eight, admitted it felt surreal even to be in the tournament after her thrilling 0-6, 6-3, 7-5 victory over Denmark's Wozniacki. Garcia, who won her last two tournaments to reach the Finals, was two points from elimination in the 10th game of the third set but she dug deep to hand Wozniacki her first defeat of the competition.

Even so, Garcia had to endure a nervy wait until Svitolina beat Halep to send her into the last four. The Frenchwoman lost to Halep but then beat Svitolina in her earlier matches. "It was kind of weird, actually, to be here. I mean, I qualified last minute, two weeks before. I wanted to keep improving like I did. That's why I think I won these two matches," Garcia said.

Wozniacki, who has been in sensational form in Singapore, described her first loss as "annoying". "I feel like I should have won that match, but it is what it is," she said. "I had the chance to serve it out and I didn't. That's really it." Wozniacki seemed headed for a third straight victory after dominating in the early stages through controlled aggression off the baseline, precise counter-punching and clutch serving.

The 27-year-old had just one unforced error in an almost flawless first set lasting just 22 minutes. But the match took an unexpected turn in the second set when Wozniacki had a time violation and argued with the umpire during the third game.

Garcia capitalised and won four straight games en route to levelling the match, before outlasting Wozniacki in a tense third set to register her first win in their three career meetings.