Supporters of Louis van Gaal's side are only getting to know names like Joe Riley and Donald Love, who both played for the first team in the last week, but for the best part of three years, they were McConnell's team-mates at United.
It didn't work out for McConnell at United, his time there ruined by injury which restricted him to just one reserve team game in his final season, so he was released last summer. But it's not working out for United this season.
McConnell, who signed for Harps before Christmas, has no bitterness towards the club and stresses that, while he didn't make the first team like Love, he did learn the "life skills" to have a good career.
"You are told at United that even if you don't make it there you have the skills to try and make it somewhere else. It was always drilled into us not to be arrogant or big-headed, to think you were better than anyone else, that you're still a person and if you work hard you'll be ok. That was the message from the coaches, how to be a good pro and work hard," McConnell told The Herald.
But the Donegal lad does feel that United are falling behind when it comes to luring the best young players around, and he also rues the fact that the family atmosphere of the Ferguson-era club he joined is no longer there.
"In my last year there, under Van Gaal, it was all very separate and you didn't get to see the senior players, it didn't feel like a family club any more," he says. "When Fergie was there it was great, everyone was in together, everyone spoke to everyone and no one was bigger than anyone else.
"Jonny Evans was great to me as we were both injured at the same time so we might be in getting treatment.
"The senior players would have spoken to you in the gym, ask how you were getting on, but towards the end, I felt they were being propelled to being like gods at the club. To me, you're the same person if you're in the Man United first team or not."
It's widely acknowledged that United have lost ground, mainly to their local rivals Manchester City, in terms of having the best young talent around. United trying to remedy that with the hiring of Nicky Butt as their head of academy.
"I think Man City are more willing to pay stupid amounts of money whereas United still want to get someone, like me, and give them a chance if they think he will do well.
"Maybe if United are after a player who is ridiculously talented they will pay the stupid money but they're not willing to do that now." says McConnell.
"United are trying to get back on track, they are still one of the top clubs but it's not the best at the moment."
Older pros bemoan the fact that trainees no longer perform tasks like cleaning boots for the senior pros. "We didn't have to do any of the old-school jobs," says McConnell, now 20.
"All we had to do at the start of the year was have a foreman and vice-foreman. I was the foreman in my second year at United, so I'd have to clean the gym, clean the classroom where we had our meetings, clean the bus. After every training session we'd have to meet the manager who'd check we had done our jobs, but there was nothing like having to clean boots."
McConnell insists that the new breed of players are not spoiled by money - not at first, anyway. "In the youth team everyone is on the same, when I was there it was around £135 a week, that's set by the Premier League. You get your digs and transport paid for so that's really spending money. It's not great money but you're only 16 and playing football so you don't need much. When you go up to a pro contract then you might have someone on £1,200 a week."
Then problems can arise. "Sometimes money can drive barriers in the changing room, a player might look at another player and ask 'why is he on that much money?' he says.
"When we were younger and we saw a foreign kid coming in, knowing he was on big money, we would be asking why he was getting so much. But it's not all about money."
He doesn't begrudge his pals their current success. "Donald Love was in the youth and reserve teams at the same time as me. Joe Riley was a year younger than me, and he's just come in, I played with Cameron Borthwick-Jackson too.
"I know most of the young lads and it's good to see them getting a chance, it's not easy. If you don't do well you have the fans on your back. Young players get away with it a bit, they can't have too much pressure on them. The boys are lucky that United have had so many injuries that the manager had to throw in the younger lads."
On reflection, McConnell admits he should have thought more before he agreed to join United, with only the Junior Cert as back-up.
"Looking back now, maybe I should have gone to a lower club where I'd have had a chance of getting into the first team, but at the end of the day you're at Man United, you're at one of the best clubs there is, learning from the best coaches. I learned a lot, not just in terms of football but in general. I have matured a lot".
He's getting to know his team-mates at Harps but hopes for a good career, maybe even a second chance in the UK.
"People take different paths when they come home from England. If you don't want to play football you can try something else, but there's nothing else for me bar what I have, the football. I have no qualifications and football is a good way to make a living, I love the game and I'd hope to have a good career.
"I don't know too much about the League of Ireland scene but I hope it will be a good season. I am looking forward to playing the big teams, that's where you can assess where you are and how good you are."