The 17-year-old is on loan at Ipswich Town from the Gunners and has got his Championship career off to a wonderful start, starting all three of his side's league games and helping them pick up seven points in the process. The winger has already made three appearances for Arsenal after making his debut as a substitute in the Champions League last season.
After creating David McGoldrick's goal on Tuesday, which proved to be the winner against Burnley, McCarthy spoke to BBC Radio Suffolk about the Arsenal loanee's talents. "Wow. The talent of him; I think he's going to play for Arsenal, there's no doubt in my mind. We are just so lucky to have him."
Of course, many great prospects have come through the Arsenal ranks in recent years - with Kieran Gibbs and Jack Wilshere being the current ones to occupy important roles in the first team. Alex Iwobi and Jeff Reine-Adelaide impressed during pre-season, while Chuba Akpom and Jon Toral have had impressive loan spells in the Football League. Many Arsenal graduates have forged good careers elsewhere, as well; Sebastian Larsson, Jay Emmanuel-Thomas, Benik Afobe to name a few.
Maitland-Niles obviously has plenty of competition at Arsenal, which makes his breakthrough unlikely at present. Theo Walcott and Alex Oxlade-Chamberlain are still relatively young themselves but Arsene Wenger has never been afraid to give young players a chance to prove themselves. Hector Bellerin got the opportunity last season and is now an established member of the first-team squad.
Talent is one thing but having the right mentality is just as important. Ipswich boss McCarthy is impressed by Maitland-Niles' attitude, though. "I had the conversation with him 'I know you can play, but if you don't run around and don't put a shift in you won't play' but he's a workaholic."
The Tractor Boys have got a fairly young squad themselves this season, which will allow Maitland-Niles to fit in easily and strike up good relationships within the squad. He seems to have settled down straight away and Ipswich fans will be looking forward to seeing him throughout the season. The winger turns 18 at the end of the month and perhaps another loan move may follow next season before he can start making a regular impact for Arsenal.