'I live by that': Kyrgios reveals unlikely inspiration

Australian tennis star Nick Kyrgios has found inspiration from an unlikely source as he continues to mature on the ATP tour.

Kyrgios remains at No.16 in the world rankings after a stellar period that saw his form increase markedly from his second-round exit at the Australian Open.

He reached three semi-finals and a quarter-final in February and March, defeating Novak Djokovic and Alexander Zverev twice each and putting up a strong fight against Roger Federer in Miami.

He then went on to contribute heavily to Australia's Davis Cup quarter-final win over the USA, defeating Sam Querrey and John Isner in straight sets.

Kyrgios turned 22 on Thursday but the celebrations were muted as he mourned the death of his 'papou' (grandfather), who he said was "always supporting, always knew the score, what was going on and even knew that Federer was the goat".

"It was a tough 24-48 hours but enjoying these special times is exactly what he would want to see," Kyrgios wrote on Facebook yesterday.

In a recent interview with Portugal's Daily Record ahead of next week's Estoril Open - his first clay tournament of the season - Kyrgios said he has learned to ignore the criticism that has come hard and fast in his career.

"It is what it is. I have to stay true to me, my family and my team," he said, as translated by journalist Jose Morgado.

"Without being rude or distracting, any other negative comment or criticism outside of that is just noise that I know is there but I can't do anything about."

Kyrgios has been known to hit back at those who spoke out against him for smashing racquets, swearing at the crowd or tanking, for which he was fined and suspended by the ATP in late 2016.

But the 22-year-old revealed he has improved his outlook after taking up the advice of a particular wartime British prime minister.

"There is an old Winston Churchill quote: 'You will never reach your destination if you stop and throw stones at every dog that barks.' And I kind of live by that now," he said.

Kyrgios confirmed he has not yet found a coach, instead continuing to lean on Davis Cup captain Lleyton Hewitt, doubles player Matt Reid and even his agent for support.

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With the French Open on the horizon, however, he has all the confidence in the world that he can continue to climb the rankings regardless of who sits in his box.

"On my day when I'm playing my game I like to think I am the best player with or without a coach," he said.