WTA Finals Semi-final Preview and Tip: Zheng can cover handicap at 5/6

• Intriguing semi-finals set in Riyadh

• Zheng is becoming the real deal

• Qinwen can cover 5/6 handicap

The final round of group stage matches at the WTA Finals demonstrated the open nature of women's tennis. There is little to separate these players on any given day.

Tournament favourite Aryna Sabalenka's unbeaten start was halted by Elena Rybakina, who may have won a dead rubber, but it should give her confidence heading into the new season.

Sabalenka held a little back in that match, and I still feel she is the player most likely to win the title this week.

The Belarusian will have to rediscover top gear against Coco Gauff, who showed strong form in her first two Riyadh matches, and has given Sabalenka plenty of problems in the past.

In the other semi-final, a less expected duo will meet for their spot in the year end final. Qinwen Zheng and Barbora Krejcikova are the tournament's 7th and 8th seeded players respectively, but are finishing the season with a flourish.

Zheng has become an elite level player

Tennis statistician Jeff Sackman runs a popular data-driven blog named Tennis Abstract and recently wrote an in-depth analysis of the improvement in Qinwen Zheng's game over the past four months in which she won Olympic gold and a hard court title in Tokyo.

According to his data, the Chinese player has become the third best player on tour. This absolutely matches the eye test.

Since an early defeat at Wimbledon, Zheng has been immense, enjoying a 30-2 win streak against players not named Aryna Sabalenka.

Her increase in form is represented in all the functional facets of her game, and importantly is noticeable across more than one playing surface. She is making her game work on both clay and hard courts.

Zheng was unplayable on Wednesday, as she walloped Jasmine Paolini for the loss of only two games. It was an exceptional level and the highlight performance of any player in the draw so far.

It was significant as Paolini had caused Zheng headaches in the past, as her pestish, fighting game had dragged the Chinese player into drawn out, complicated contests.

The Italian had absolutely no answer to Zheng's power and precision. Paolini has been playing in the doubles tournament too, but even with less tennis in her legs it is difficult to imagine another outcome.

After that win Zheng said of her form, "Finally, I showed off some tennis I really want to play. Of course, when you enter the match you are nervous but at the same time you feel confidence because you know your level. And I know how capable I am."

Confident, and potentially ominous words.

Krejcikova got the job done

Barbora Krejcikova deserves credit for her run in Riyadh.

Expectations were low for the Czech who did not qualify as one of the top eight players of the regular season, but as the winner of a Grand Slam during the season.

Clearly her Wimbledon victory marks her as a dangerous, highly qualified talent and victories over Coco Gauff and Jessica Pegula have justified her wild card selection.

To defeat Gauff in straight sets was highly impressive as she was the only player so far that was able to exploit the forehand and serving volatilities of the young American's game.

Her craftiness got the job done, but managing the consistent power of Zheng is a whole different proposition.

Krejcikova was a set and double break up against Iga Swiatek in her first Riyadh match, but was blown away by the Pole once she gathered a head of steam. There was nothing she could do to blunt the sharp weapons of Swiatek.

I fear a similar outcome could transpire here. Zheng has the ability to take the match out of Krejcikova's hands. Zheng's attacking execution is getting better by the match, and if she can repeat what she is capable of then she will likely have too much today.

Furthermore, Qinwen Zheng has benefited from an extra day of rest than Krejcikova, having played her previous fixture on Wednesday whilst Krejcikova had a mentally demanding match against Gauff on Thursday.

Krejcikova had to get a result in that match, but it required a huge level of effort to get over the line and the pressure looked to be getting to her on several occasions. Despite being in control of both sets, Krejcikova stumbled over the finishing line in both sets facing break points when attempting to serve it out and being broken in set one.

Of course, she survived and was a deserving winner but she flew a little too close to the sun for her win to be considered comfortable.

Zheng has a lot in her favour

When you consider her extra rest, the strong form shown across recent months and the performance levels demonstrated in the group stage matches it is clear that Zheng is a deserving favourite for this match.

I feel that Krejcikova's chances may again rest in finding her way into an early lead. She was able to do so against Gauff, but with the shorter turnaround between matches and the mental energy expended so far there seems to be more routes to victory for Qinwen.

In this situation I think it is smarter to side with Qinwen Zheng on the -3.5 game handicap line as whether in two sets or over the distance I expect she will assert her superiority.

Back Qinwen Zheng to win -3.5 game handicap at 5/61.84.

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