David Avakian: You played Serena Williams in 1999 and 2009, and now in 2019 she is still playing. You must be as impressed by the fact that she is still going strong...

Kim Clijsters: Absolutely. The start of her first match wasn't great, but time and time again she is capable of lifting her level. That's enormously impressive. The way that she keeps fighting, improves, got fitter after her pregnancy, and is able to keep finding motivation is amazing.

Back in 1999, when you played her for the first time, did you already understand that you are facing a very special girl?

KC: I did, also because there was hype around her and her sister Venus. Their father shielded them from the circuit so to speak and decided to keep them away from junior tennis tournaments. The hype and high expectations were already there. I remember our meeting at the US Open in 1999 very well. I was leading 5-2 in the third set but couldn't hold on to my lead. I got nervous and she suddenly started hitting more aces and played with more precision when she needed to. Back then she already had that quality in her. We have had many great battles. I'm definitely very impressed that she is still around and reached two Grand Slam finals last year.

We have to mention 2009, when you played her in the US Open semi-finals, a rather explosive match that you ended up winning. Do you think back to that match a lot?

KC: Not really. Every now and then when other incidents occurred involving Serena, international press approaches me to comment on it. For example, last year when she played Naomi Osaka in that controversial US Open final. Those moments felt strange to me. On one hand you want to be focused on what you have to do, but on the other hand you want to understand what is going on without getting distracted because the match is still going. They were difficult moments. The way Naomi Osaka dealt with it was very nice. During the last year Naomi has grown up and she is going to become a great player. 

Serena has become an international icon to many. Do you agree with that status?

KC: Oh yes. She transcends the sport of tennis. She is bigger than the sport. Not many people can say that. On all fronts she is a role model, not just for young tennis players, but also for mothers and women all over the world. She is playing that part beautifully, together with her sister. What Venus has been doing lately, considering her illness (Sjögren syndrome, red.), is unbelievable. They have their separate stories, highlights and crises. What they have been through is not to be underestimated. For them to continue fighting at the highest level is very impressive.

You mentioned motherhood, something you share with her. You even preceded her in that regard by coming back (successfully) to tennis after having a child. Serena's comeback has been good too, but she hasn't quite reached the old Serena levels yet to win a Grand Slam tournament. Do you think she will be able to take that one extra step it takes to win a major again?

KC: I think she will. I do think she returned to the tour a bit too soon, but she probably decided that she doesn't want to lose time. After pregnancy your body needs to adapt and mentally and emotionally your life changes a lot. It's not easy to just continue where you left off before having a baby and act as if nothing happened. I think that at the moment we are seeing the fittest Serena since her pregnancy. She is working very hard on it, something she has been very open about. She admitted that she needed to lose weight to be able to move better and faster on court. 

She does struggle with a knee injury it seems. Does that worry you?

KC: I am not sure to be honest. It's something that can happen to anyone. Maybe when you look at it scientifically you could explain that issue through hormonal changes affecting her joints. But honestly, I don't know. And she is not the youngest player out there anymore. There's a bit of wear and tear on the joints and her entire body as well. But generally, we don't see her taped up that often. Looking at how she has played in Paris so far she seems fine to me. It will be interesting to see what happens when she has to play a couple of tough matches in a row. Will she be able to recover?

She played Kurumi Nara today in a match that you were commentating on. What were your thoughts about that match?

KC: I think it was a fun match to play for Serena, against someone who is really good at playing rallies, but at the same time doesn't have the firepower to blow her off the court. The match was in Serena's hands and she kept improving as the match went on. Her returns were really aggressive, she was able to find the corners quickly and keep the points short. I have noticed that since her comeback she is really trying to keep the rallies nice and short. 

There's always a lot of talk about favourites. Should Serena always be included in these lists?

KC: At this point she is definitely still one of the favourites to win big titles. There are around five girls with a good chance to win Roland Garros. I'm talking about Simona Halep, followed by Naomi Osaka, Karolina Pliskova, Sloane Stephens and Serena.