"It was pretty difficult at the start, especially with games every three days," Mooy said. "You play Saturday, Tuesday, then another game Saturday. Then you might have a week off.
"At the start, even the training was more intense and I just felt tired all the time, then your body adapts and you pick up the game speed. So many games, though, that was the hard thing. Then because you're playing so many games, it's not just physically, it's emotionally.
"Because you're investing all your emotions into the game and you might win one day and be really happy, then a few days later, you might get beaten and you're down. It's a rollercoaster."
True, but also a necessary initiation before tackling England's top flight.
"It's made me a strong person and a better player. I took a lot out of the season," Mooy said. "You want to test yourself against the best players in the world and hopefully next season I get the chance to enjoy it."
Of Australia's three Confederations Cup group opponents in Russia, Mooy has played Germany once - a 20-minute cameo in the 2-2 friendly draw of 2015.
That he wasn't a part of the 2014 World Cup squad when the Socceroos last faced Chile underlines his astonishing progress.
At that point, he'd just left Western Sydney for Melbourne City in a move that would provide a springboard all the way to the top.
One catalyst was a shift from defensive midfield to a more advanced role that liberated the incisive attacking vision now in high demand.
The other was City Football Group's penchant for shrewd business. By signing Mooy for free from the Australian sister club they bought for around A$11 million ($11.5 million), and then loaning him straight to Huddersfield, Manchester City will make a tidy A$16.7 million ($17.5 million) profit off a player who did not appear once in a blue shirt.
The in-principal deal would far and away be Town's record signing ahead of the 1.8 million paid for defender Christopher Schindler last year.
And boasting a value essentially on a par with the A-League's combined salary cap, Mooy would trump the transfer sums of Australian legends Mark Viduka, Mark Bresciano and Harry Kewell.
"It's been a crazy year that worked out perfectly," Mooy said. "Sometimes you think it's never going to happen, you have doubts creep in.
"But you dream of stuff and believe in it - and it happened, so I have a lot of faith now."
- AAP