Dubai Tennis 2019: Belinda Bencic and Hsieh Su-Wei target more shocks against Elina Svitolina and Petra Kvitova in the semi-finals

We are down to the final four players at the WTA Duty Free Tennis Championships as the semi-finals take place on Friday. Here is a breakdown of the two matches at the Dubai Duty Free Tennis Stadium and what to watch for. Kvitova, the 2013 Dubai champion, put in her best performance of the week on Thursday when she swept past Viktoria Kuzmova 6-4, 6-0 in the quarter-finals. The Czech, who had two early matches at 11am on both Tuesday and Wednesday, looked much more comfortable in the late afternoon sun on Thursday and she is understandably favourite to reach the final. But she would be unwise to take Hsieh lightly after the Taiwanese player's sensational comeback on Thursday against Karolina Pliskova. She was 5-1 down in their quarter-final but won six games in a row to reach the last four. It was a great effort. How much it took out of her physically could be telling, but her determination means she will be a real threat to the world No 3. Kvitova has won all three of their previous clashes, most recently in Sydney in January, and is yet to lose a set to the 33 year old. Svitolina is just two wins away from a historic treble in Dubai. The 2017 and 2018 champion can be the first woman to claim the Dubai crown three years in a row and it is hard, on current form, to see anyone stopping her. Since a slow start to her opening match against Ons Jabeur on Tuesday the No 6 seed has been on sensational form. She dropped just three games in sweeping past two-time major winner Garbine Muguruza on Wednesday and then on Thursday lost only five games against Carla Suarez Navarro. The Ukrainian has won 12 matches in a row in Dubai and Bencic will have to produce something special to stop her. But that will not faze the Swiss who has already knocked out two seeds with brave comeback performances. She survived six match points before beating Arnya Sabalenka on Wednesday and then less then 24 hours later she shocked world No 2 Simona Halep 4-6, 6-4, 6-2. Bencic, who was as high as No 7 in the world back in 2016, is down at No 37 now, although that ranking will move up after this week. She has played with real spirit and confidence but she will need to produce her best tennis yet in Dubai if she is to prevent Svitolina reaching the final. Bencic can take some heart from winning their only previous meeting in 2014, albeit it was on clay in Charleston.

Dubai Tennis 2019: Belinda Bencic and Hsieh Su-Wei target more shocks against Elina Svitolina and Petra Kvitova in the semi-finals

It is semi-final day at the Dubai Duty Free Tennis Championships with the tournament's two surprise packages looking to keep it going to reach Saturday's final