MELBOURNE, AUSTRALIA - JANUARY 20: Maria Sharapova of Russia plays a forehand in her second round match against Aliaksandra Sasnovich of Belarus during day three of the 2016 Australian Open at Melbourne Park on January 20, 2016 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images)

Rafael Nadal, Tomas Berdych, Kei Nishikori, Angelique Kerber and Belinda Bencic have had their say on Sharapova's positive doping test at various press conferences this week.

Nine-time French Open champion Rafael Nadal said it is a bad look for the sport.

"It's terrible news for the world of sport in general and for our sport. I think it's terrible because the sport must be clean and must look clean. The good news about this is that we have a good anti-doping program, [and] that the players who are not doing the right thing are going on a trial," Nadal said.

"I am 100 percent confident with my team, and at the same time, I know all the things I am taking. It is difficult to imagine that something like this can happen, but everyone can make mistakes. I want to believe that for sure it was a mistake for Maria, that she didn't want to do it, but it is a result of negligence. But the rules are like this, and it's fair, and now she must pay for it."

Top ten players Kei Nishikori and Tomas Berdych echoed Nadal's sentiments.

"I was surprised and very sad to hear that she was taking something that she shouldn't take. It's very sad for tennis, even men's tennis. I don't know many details, so I can't say much, but maybe she has to take care a little more with her team," Nishikori said.

Tomas Berdych was even more scathing of Sharapova.

"If you are not taking anything then you don't have to look at the list, right? So if I'm supposed to take any medicine, whatever it is, and it's new and that I haven't taken in the past, the No. 1 thing I'm going to do is check it 10 times, all the different sources, doctors, this that, everywhere I can, before I start using. And then I will find out what's new with WADA and the list," he said.

Angelique Kerber: "It's a combination of (me and the team). At the end, I'm checking everything twice, or three times, to see if it's really on the list because every player has a responsibility to yourself."

Belinda Bencic: "I opened that email (from WADA) at the end of December. We all got an email. ... I look at the list, especially when I'm feeling a little bit sickly and check and look what is inside there and see if it's not forbidden."