The first time you qualify for the season-ending tournament, you feel as though you're part of the elite. You're no longer a pretender. You're a star. So that's pretty cool.

That's how Naomi Osaka will be feeling now after qualifying for this month's BNP Paribas WTA Finals Singapore presented by SC Global. In the final days of the Porsche Race to Singapore, other players are still chasing the remaining places in the eight-woman field. But Osaka's already guaranteed to be there and I'm sure she'll be very happy about that.

Osaka's been the story of the season, because of where she's from, and also because of the speed of her rise with her victories at Indian Wells and, of course, at the US Open. She'll be one of the favourites in Singapore. And, more importantly, it means the singles tournament will have a player from Asia. That’s because Li Na retired and never made it to the WTA Finals after the event moved to Singapore. But now, with Osaka among the leading eight players in the world, the whole continent has someone to cheer for.

Read more: Martina Navratilova: Osaka reminds me of a young Serena

Osaka won Indian Wells almost out of nowhere. And then, just when it looked as though her summer was going to be a disaster, she won the US Open. It's been an up-and-down year for Osaka, but the ups completely overshadow the downs, needless to say. And I don’t know if anyone could have handled themselves better in the US Open final.

It was astonishing the way Osaka conducted herself, showing such great emotional control, and holding it all together under very difficult and unusual circumstances, with her biggest title in sight. And now that she has come through that so well, she will be ready for anything and everything. Because whatever might happen on the court in the future, it is going to seem like a piece of cake. That experience, as emotionally wrenching as it was at the time, will now be a big positive for her - it can hold her steady in Singapore and for the rest of her career.

Playing at the BNP Paribas WTA Finals Singapore presented by SC Global, you have the opportunity to end the year with an exclamation point. Petra Kvitova has already had a fantastic year - now she can make her season even greater by winning the Singapore title. After the attack in her home, we weren't even sure at one point whether Kvitova would be playing again and yet here she is, an elite player once again. Kvitova has not just been competing, she has been winning titles, and for that we are all very grateful.

Some players can be too complacent but, if anything, Kvitova gets too fired-up at the big tournaments. She knows she needs to relax a little bit so she can allow herself to play her best. She tries so hard and it means so much to her that it sometimes gets in the way. But, for me, that's a nice problem to have.

Like Osaka and Kvitova, Simona Halep, Angelique Kerber and Caroline Wozniacki have already qualified for the WTA Finals, but for a few players the Race continues behind them as the last three spots are still up for grabs. Every point and every match matters in the Porsche Race to Singapore. You could miss out on qualification by just one more match, just one win somewhere, anywhere during the year. Just one more match! Financially, it's a huge potential windfall and it's fantastic to be at an elite tournament so to miss out on getting there by a whisker, well, that would be a tough pill to swallow. So who will grab this opportunity?

Read more: Porsche Race to Singapore Update: Final qualification spots set for photo finish

If I were Sloane Stephens, I would be chomping at the bit to play in Singapore, as it's a great surface for her. It's slow enough that you can run down a lot of balls, but Stephens has enough power to still be able to hit through the court. It's a defender's court in Singapore, and that means it's a great opportunity for her. If Stephens can win the title, she would turn this into a great year. She made the final of the French Open, but she lost to Halep, so she has just come up a little bit short in 2018 so far. If she qualifies for Singapore, which is just behind the majors in terms of importance and prestige, Stephens could end the year on a high note.

Qualification would also give Elina Svitolina the chance to salvage her season. The court in Singapore is perfect for her. She hasn't previously been able to break through at the majors or at the WTA Finals, but if she makes it to Singapore, and finishes as the champion, that would be a great end to the year, and would set her up for next season as well.

Karolina Pliskova is also in contention in the Porsche Race for Singapore. After she reached the final of the 2016 US Open, we thought she would have won one of the majors, or the WTA Finals, by now. But surprisingly Pliskova hasn't got to a major final since. It's disappointing that after having been so high - she was WTA World No.1 - she hasn't been able to stay near that level. I don't know why Pliskova has not quite lived up to our, and most likely her own, expectations. I do know that every time she hits the ball, I'm holding my breath as I'm not sure whether it's going to be a great winner or a loose error. I mean Pliskova does hit a pretty flat and hard ball, but that the only reason?

I know Pliskova is switched on on the inside, but from the outside it almost looks as though she doesn't care. I know that's not the case, but that's how it looks. As calm and relaxed as Roger Federer seems between the points, you can totally see and feel the intensity during the point. I sometimes don't see that intensity, that urgency, during the point with Pliskova. You can be smooth and still intense, it's a fine line. If you get too intense and too muscular, then you don't flow, and you can lose your rhythm and smoothness. And conversely if you are too relaxed and loose, well, that won’t work. Tennis is such a dynamic, explosive sport, and I feel as though Pliskova just hasn't found that perfect balance between relaxation and intensity yet.

What a story it would be if Aryna Sabalenka plays in Singapore. She has to make up points on Kiki Bertens and Pliskova but mathematically she has a shot. We knew the raw talent was there but it's been a meteoric rise. I really love what her coach, Dmitry Tursunov, is doing with her. He was also a real talent as a player, though I don't think he quite reached his potential. And maybe he recognised Sabalenka's talent and saw in her that she could be a top player winning the majors if she just tries to put it all together and boy has she been doing that. She has come of age really quickly. She has firepower and she is learning to control it. Sometimes Sabalenka gets a bit too fired up. Nice problem, though - I think it’s easier to control emotion than to create it.

Read more: 'Her life has been a whirlwind recently' - Tursunov speaks on Sabalenka

Bertens is another player who has made major improvements in her game this year and she could very well end up in Singapore.

Whatever the field we get in the end, I'm sure it will be a fitting end to another great and unpredictable year on the WTA Tour.