Tennis star Nick Kyrgios recently spoke about his struggles with depression, self-harm and substance abuse.
Kyrgios's revelation came as he described the condition of his mental health around the time of the 2019 Australian Open.
They were dark moments for Kyrgios that Australian Davis Cup captain Lleyton Hewitt had been aware of for years.
"I've spoken to him consistently every few weeks over the years," Hewitt said.
"I understand the tough times that he's been through in the past.
"It's hard when you are always out as the centre of attention and people assume all the time that everything is rosy and it's not."
Hewitt said he regularly spoke with Kyrgios during the COVID-19 pandemic.
"I get along extremely well with Nick," he said.
"We have plenty of open discussions. The last two years have been tough for him.
"Nick enjoys being home and he doesn't like travelling all the time and it's tough being an Australian player, especially with the pandemic, and not being able to come back [to Australia].
"It's been tough for all of the Aussie players and they're not in the best head space."
Kyrgios has said he was in a much better place now, which was evident during the Australian Open when he claimed the men's doubles title alongside close friend Thanasi Kokkinakis.
But he is a notable omission from Australia's Davis Cup squad for its qualifying tie against Hungary, which takes place in Sydney on Friday and Saturday.
Hewitt denied reports Kyrgios was overlooked for selection, saying he wanted the 26-year-old in his squad.
"For us it's disappointing that he wasn't available for this particular tie, but he's [in] the top five players in our team," Hewitt said.
"He loves playing [Davis Cup] but he has a lot of other things going on at the same time as well."
Hewitt said he was hopeful Kyrgios would represent Australia if the squad advanced to the Davis Cup finals in November.
"Hopefully he gets the opportunity to be back in the team because he really enjoys being around the boys and I think it helps his tennis and his enjoyment of the sport as well," he said.
"At times it can break up a really long year. Tennis is a pretty individual sport most of the year with the 12 months travelling.
"Hopefully we get through this match and he's available later in the year."
Kyrgios not 'driven by the majors'
Kyrgios was ranked as high as 13 in 2016 and he has beaten the likes of Novak Djokovic, Rafael Nadal and Roger Federer during his career.
But critics believe the Australian's lack of consistency has let him down.
Before he was knocked out of the Australian Open singles by eventual runner-up Daniil Medvedev, Kyrgios had only played sporadically over the past two years.
He is currently ranked 134 in the world.
"It's lucky for him as you can see with the Australian summer he can go out there, pick up a racquet and compete with the best players with very limited matches under his belt," Hewitt said.
"Not many players can do that."
Hewitt said Kyrgios needed to spend more time on the court.
"For him to get to his absolute best he does need to get those matches, absolutely," he said.
"In a lot of ways, he plays for different reasons than a lot of other guys.
"He is not driven by the majors and winning titles. Sometimes it's for the entertainment and the enjoyment."
