'It's giving her MORE energy': Naomi Osaka's coach lauds star for 'UNBELIEVABLE' strike to support racial injustice protests

US Open favorite and social campaigner Naomi Osaka is a "role model" for people with an impressive attitude on the court, her coach has claimed after she pulled out of a tournament and wore specially designed masks at the US Open

Osaka has reached the quarterfinals in New York while walking on court wearing different masks as she takes a stand against racial injustice in the US, each dedicated to an individual who has suffered.

The Japan-born, US-raised 22-year-old also pulled out of the Western & Southern Open in Cincinnati in protest at the police shooting of Jacob Blake in Wisconsin before changing her mind to reach the final.

“It’s a very important topic for her," explained Wim Fissette, the former coach of the winner of the tournament, Victoria Azarenka, after Osaka ultimately pulled out through injury.

"She did an unbelievable, big thing during the Cincinnati tournament. We support her there because we know how important it is."

Osaka, who is preparing to face Shelby Rogers for a place in the final four, is anything but the "unprofessional 101" she jokingly describes herself as on social media.

“It’s definitely helping her and giving her even more energy,” Fissette said of her campaigning, having started working with Osaka at the end of last year.

“She always has the motivation. Of course, she wants to go really far in this Grand Slam, and obviously she wants to win it. But this is like an extra motivation.

“With wearing the masks, she wants to be a role model. But she also knows that it has to go together with the role model on court. So it’s a good combination.

"Role model off court; also great attitude on court. So far it’s working really well. I’m very proud of her.”

Addressing her Instagram following of more than 1.3 million on Monday, Osaka pictured herself in a mask honoring Trayvon Martin, a 17-year-old African-American high school student who was fatally shot in 2012.

"I have a lot to say about this," she explained.

"I actually didn’t wear hoodies for years cause I wanted to decrease the odds of 'looking suspicious'.

"I know his death wasn’t the first but for me it was the one that opened my eyes to what was going on. I remember watching the events unfold on TV and wondering what was taking so long, why was justice not being served.

"To see the same things happening over and over still is sad. Things have to change."