Still just 21, he is built like a brick outhouse and, as several members of the Hartlepool United and Burton Albion teams can confirm, tackles like one too.
But beyond the deadpan humour and physicality there is a young man busting a gut to get to the top.
He spent more than a day on aeroplanes as he flew back to Sydney from competing in the AFC Under-23 Asian Cup with Australia in Uzbekistan and then onto Portugal to meet up with his new team-mates at their summer training camp.
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“I haven't had a break because I was playing in the Asian Cup that finished on June 22, and from there I flew to Australia for two days, then headed to Portugal. The jet-lag has been hard, it was about 27 hours on the plane, and three hours in layovers, so it's good to be on the ground,” he says, speaking at the Amendoeira Golf Resort.
"I was meant to have five weeks off but then I got called up for the tournament but at the end of the day I just want to play football so I'm not going to complain too much."
Miller’s move to Hibs was not so straightforward, the full-back having signed a pre-contract arrangement with Macarthur before being made aware of interest from the Capital club.
"It was funny because I signed the pre-contract but luckily for me, Hibs knocked on the door and I was like, 'yeah, 100 per cent' then had the tournament with the under-23s.
"We did alright, came fourth which we needed to get into the Olympics so we got the job done. It's a shame we couldn't finish any higher but it's a tournament and it comes down to whoever is the best on the day."
Like many of his compatriots, Miller’s plan was to leave the A-League to further his career.
"I just wanted to get a move to Europe. I love playing in Australia; it's close to home and my family and friends, but I want to really push myself, and challenge myself, and to get to the next level I had to get an overseas move.
"The Scottish Premiership, from what I've seen, is a great league and I'm keen to get started."
Miller will be the eighth Australian to move to the top flight, joining Nathaniel Atkinson, Cammy Devlin, and Kye Rowles at Hearts, Dylan McGowan at Kilmarnock, Phillip Cancar at Livingston, and St Mirren duo Keanu Baccus and Ryan Strain.
“Obviously they're doing something right in Scotland,” Miller laughs.
"I'm just delighted to be here and can't wait to get on the pitch."
Miller was rooming with Ryan Porteous, Kevin Nisbet, and Kyle Magennis in Portugal – ‘a rowdy bunch, but they helped me settle in well’ – and only has positive words for the rest of the squad.
"It’s what you need with a group like this. You've got to be a big unit and do whatever you can to get around each other and make sure that you're playing your best football."
He has his heart set on a city-centre flat, too.
"I'm going to get a place in Edinburgh and I think my dad will come up for the first few weeks to help me settle in and be around so I can have that connection and keep my head in the right space and we'll go from there.
"I've heard Scotland’s freezing, but I like playing in the cold, it's not like the training camp where we were playing in 30°C heat."
He credits the Covid-19 pandemic with helping him become the physical specimen he is today, and well-suited to the Scottish game.
"When corona hit we were off training for about three to four weeks and I was in the gym nearly every single day, I was eating right, and I just got bigger, and bigger, and bigger,” he explains.
"The second football came back along I had just leaned down completely, gained a good size, and luckily maintained my pace so, happy with that!”
It’s not all about pace though. As alluded to previously, Miller likes – no, loves – a meaty, but legal, challenge.
"The Scottish Premiership is very, very physical so it's been hugely beneficial. I'll be able to match anything that comes my way.
"I love a tackle. The ball is there to be won and you've got to win it, no matter the circumstances. I love football and I want to play at the top level and I know I can kill it here at Hibs and help the team be successful and play as high as we can.
"For defenders, big challenges and keeping the winger on the floor means you know you've done your job.”
Miller doesn’t even have a past in Aussie Rules to explain his love for a tussle.
"Aussie Rules is one of the biggest sports in Australia, it's just hard-hitting and whenever you're on the pitch you just give it 110 per cent and forget about everything else that's happening around you and you're in the zone and give it all you've got but it’s always been football for me, haven't done anything else since I started as a 12-year-old.
"That's why we get signed, that's why we're on the pitch, we just want to kill people, win win win no matter what.
"When you're playing with that sort of adrenaline you go even harder. Fingers crossed for no cards but I'm not going to hold back, I'm going to give it everything I've got. You think I hit hard in the pre-season games, wait until you see me in the Scottish Premiership,” he finishes, practically rubbing his hands in anticipation.
And that’s a promise, rather than a threat.