Kiki Bertens, the Dutch world number 10, is the latest WTA Tour star to feature in a BBC Sport column. In her third piece at the Australian Open, the 2016 French Open semi-finalist talks about matching her best run in Melbourne, her sadness at hearing Dutch wheelchair legend Esther Vergeer is fighting cancer and whether there should be a punishment for 'unnecessary' medical time-outs.

If you didn't see my second-round match in the Australian Open then that's a good thing - it was not a great one from my perspective!

The most important thing was that I won and I still managed to do that in two sets against Australian wildcard Arina Rodionova, despite not being at my best.

That win puts me into the third round in Melbourne for only the second time in my career so I'm very happy about that.

Now I will play Kazakhstan's world number 73 Zarina Diyas on Saturday for a place in the fourth round. Reaching the last 16 would be my best ever run here.

I've played Zarina once before when she beat me in Tokyo four years ago - that's quite a long time ago in tennis terms.

I think I'm a different player now, as I've explained in my previous columns, but she is playing really flat so that makes it tricky.

Against Rodionova, I wasn't at my best because my legs weren't moving that great.

That had nothing to do with the Achilles injury which forced me to pull out of Adelaide last week and which I am continuing to manage.

My side-to-side movement was really good and I got a lot of balls back in the court. It was more like when I had opportunities to come forward I wasn't really going through the ball with my legs.

So I stopped doing that and I was just trying to make as many balls as I could and let her finish it.

The injury did not bother me at all, but my team and I are still trying to find a balance so it does not become a bigger problem. That's why I decided not to play doubles here.

Sometimes I like to play doubles to get some matches in, I know the more matches I play the better the level of my tennis is going to be.

But at the moment my recovery is helped by the day off between matches, meaning I can rest and have just a light practice to be ready again for the next match.

I played alongside Australian world number one Ash Barty in Brisbane earlier this month and I loved playing with her, especially in her home town.

It would have been an amazing experience to play with Ash here, but it was the best decision physically not to play in the doubles.

Players need to consider if they really need medical timeouts

Earlier this week the issue of tactical medical timeouts was raised again when Caroline Wozniacki questioned why Dayana Yastremska used one at a crucial point towards the end of their second-round match.

Obviously taking a medical timeout is allowed at any stage of the match and you can do what you want to do.

I don't exactly know what happened in this situation and maybe it was a genuine injury.

I would like to see a rule change - or at least a discussion around the issue - where you can have an injury timeout but then you lose a point.

I think it needs something to make players consider if they really need the timeout.

I was sad to hear Dutch legend Vergeer's cancer diagnosis

Earlier this week I read the terrible news that Dutch wheelchair tennis legend Esther Vergeer has been diagnosed with breast cancer.

Esther won an incredible 470 successive matches between 2003 and her retirement in 2013; that is why she is one of the biggest names in sport back home.

It is always really sad when you read something like that but it was good to hear her say she is full of positive energy.

I have met her on a few occasions and we know each other to say hello.

She is a huge star in the Netherlands and what she did for the sport in our country is unbelievable.

Diede de Groot is now the women's number one wheelchair player in the world and I think that is partly because Esther made the sport so big and inspired so many good players.

Esther is loved back home and means a lot to the people. She has done a lot for sport in the Netherlands and now she is chef de mission this year for the Paralympics in Tokyo so she is still really involved.

I wish her all the best in her fight and hope she returns to full health soon.

No time for an escape room, but I have been to the casino

Melbourne is a great city and one of the favourites place on tour for many players.

I've been playing and practising a lot - which is a good thing, of course - so I haven't done much yet around the city, other than a few dinners.

On Wednesday night we had a special dinner; actually, it was the birthday of my coach Elise Tamaela.

We went to Nobu - which is a favourite for the players - and that was a really nice celebration.

We got Elise a cake and it was brought to the table so we could sing 'Happy Birthday' to her. She was really happy with that… not!

Also I went to the casino one night with my team, although I don't play too much.

I just like to walk around and look at what is happening. It means we don't lose too much money!

I like to play a little bit of blackjack and a little bit of roulette but I'm not a big gambler.

One thing I really love doing is an escape room. We did that before I arrived here in Melbourne and we are definitely planning to do one here when we get the time.

But hopefully not too soon because that will mean I'm still winning!

Kiki Bertens was speaking to BBC Sport's Jonathan Jurejko at Melbourne Park.