After a frustrating cameo appearance against Swansea City last weekend, the Australian international spoke of his excitement at the prospect of the encounter.
Speaking to the media ahead of the game, Mooy declared games against the likes of United was the reason why the he came to England.
The 27-year-old also spoke about growing up watching Premier League football and how David Wagner's men could spring a surprise during his pre-match interview with the full transcript below.
On achieving 'extraordinary' results with Huddersfield Town
To be in the Premier League is massive for the club and the town as a whole and one we are all enjoying and learning from.
On continually aiming for the 'extraordinary'
We've just got to go into every game and try and win it – otherwise what is the point? It's still early doors for us in the Premier League but we're just trying to make the most of it and prove we are good enough to be here.
On the chances of beating Manchester United
That's the beauty of football – anything can happen. They are obviously a massive club and it's a big game but we've got to go into it believing in ourselves and trying our best.
Hopefully we can get a good result which would be amazing - of course it doesn't happen every week but sometimes you do see the smaller teams beating the bigger ones.
But to do it we'll have to be at our very best - we have to believe we can get a good result; every player needs to do their jobs and hopefully we can perform well as a team.
On the game plan against Manchester United
Manchester United are a good team, they'll be right up for it and will want the three points as well.
They will be very difficult to play against but we have to be at our very best and have a big performance.
Little mistakes can prove costly in this division so we have to eradicate them but we also have to be more threatening in the final third as well.
On the excitement from the fans for the clash
It's a special game for everyone but every game is a massive one for us – every one is important but when you play the big clubs then it is always very nice.
On the dressing room mood ahead of the game
It was a bit down at the start of the week (after Swansea City) but we've got over it now and looking forward to the game tomorrow – it should be an exciting match and hopefully we can put in a good performance.
On not starting at Swansea City
Of course every player wants to start every game but it's ultimately the manager's choice and I am 100% behind him and when I do play will just try my best.
On expectations (or a lack of them) ahead of the game
We have to go into every game believing we can get a good result otherwise there is no point in us being there.
On playing against the best players and teams
This is why I came to England – to push and test myself and see how far I can go - if I didn't want to do that then I would have just stayed in Australia.
These are the game you want to play in - when you're younger you always dream big and it's taken a long time to get here but I never gave up and now I have the opportunity to prove myself so I am very proud.
On learning from playing the best
Against the better teams like Tottenham Hotspur you learn just by being on the same pitch and I just want to keep picking up stuff and becoming a better player because of it.
We have to show we have learnt something from that game (against Manchester United) and made some steps forward – we need to try to make it a more competitive game and not as one-sided as that one.
But you come up against good players all the time in this league and just have to try to concentrate on your own performance.
On watching Premier League football growing up
Manchester United is definitely one of the biggest clubs in the world – you always saw the big names in Australian football like Harry Kewell and Mark Viduka and knew when they were playing on TV.
I watched every team growing up and didn't just pick one to watch and follow – I just tried to watch as much as I could and the Premier League was the main league that was on all the time in Australia.
On re-adjusting to the Premier League after international duty
It's difficult – you are in a completely different timezone and it knocks you about a little bit. But it's something I just have to get used to, accept and try to be in the best possible shape you can for the upcoming games.
It's a bit better this year as there are less games both internationally and in the Premier League compared to the Championship.
On Australia's recent World Cup game against Syria
It was a very tough game – especially the away leg where the conditions were very humid and the pitch wasn't very good at all.
That's what happens when you play these sorts of countries - you're up against it a little bit and then when we got back home for the return leg we played well but we just couldn't score - luckily we got a winner at the end though.
On the expectation levels for Australia in the World Cup
We have the pressure on us to qualify because we've been to the last three World Cups so the people are expecting us to qualify and improve every time.
It's every player's dream to play in a World Cup and I'm no different.
It's a big goal of mine to do and hopefully it will happen but I've just got to focus on one game at a time.