Alex de Minaur's sweet moment with girlfriend after win at Australian Open

Alex de Minaur appears to have found happiness on and off the court, spruiking his new mantra after a dominant win in the first round of the Australian Open. The top-ranked Aussie was in fine form on Tuesday night, taking down Taiwanese qualifier Hsu Yu Hsiou 6-2 6-2 6-3.

With British girlfriend and fellow tennis player Katie Boulter watching from the stands, the Aussie star made an impressive start to his sixth Australian Open campaign. The World No.24 is the only seeded Aussie in the draw after Nick Kyrgios' withdrawal due to a knee injury.

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And while mentor Lleyton Hewitt used to listen to 'Eye of the Tiger' to pump himself up, de Minaur has revealed he's been taking a different approach. The 23-year-old explained during his on-court interview that he's been listening to the Bobby McFerrin hit 'Don't Worry Be Happy', released about 10 years before he was even born.

"I've got that song in my head at all times," he said while also revealing he's written the slogan on his racquet bag. "I'm listening before I step out on court, I just want that message ingrained in my head.

"Whenever there's a tough moment out there, I just kind of try to sing that song in my head and avoid any negative thoughts and try to stay positive out there."

De Minaur's best run at the Australian Open came last year when he made the fourth round. He recently brought former Australian Davis Cup player Peter Luczak into his coaching staff, joining head coach Adolfo Gutierrez in an attempt to unlock his full potential. 'The Demon' said Luczak has contributed to his new-found positivity.

"We started at the start of this year but I've known Peter for a long time and we've done a lot of Davis Cup matches together," he said. "It's been good to have him around as he's keeping a very positive mindset, keeping kind of me calm.

"I tend to be quite hard on myself. So he's kind of trying to remind me that I'm doing well, that I'm doing the right things, and to kind of enjoy every second out there."

Alex de Minaur's sweet moment with Katie Boulter

Also contributing to his newfound happiness is girlfriend Boulter, the World No.120 from Great Britain. Channel 9 cameras captured the moment de Minaur and Boulter shared a sweet embrace in the locker room after the match on Tuesday night.

De Minaur looms as Australia's biggest hope at his home grand slam, following the injury withdrawals of Kyrgios and women's No.1 Ajla Tomljanovic. Ash Barty's retirement has also left Aussie tennis with a sizeable hole to fill.

"I've been in this position a while, in Davis Cup obviously and I kind of cherish it," he said. "I know what is asked from me - I know that at times I've got some pressure on myself to deliver. I take it with pride ultimately.

"We're in the second round and there's still a long, long way to go but I try to look at it more as me individually and try to focus on my goals and get as deep as I can. That's the goal - get deep, enjoy myself and keep getting better every day."

The Aussie star came into the grand slam full of confidence after beating World No.2 Rafa Nadal at the United Cup in Sydney earlier this month. He also beat two-time Australian Open runner-up Daniil Medvedev at the Paris Masters in November.

"I knew it was going to be a tough match but I'm just happy to be here in Australia, playing in front of you guys," he said. "It doesn't matter who I play, I'm going to be up for it - you guys just bring the energy, I'll be ready. I've got a lot of confidence - I knew I had that level for a while ... now I know I can do it every week."

with AAP

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