At the tender age of just 18, having previously only played for the Development Squad in Premier League 2, the young midfielder held his own against established internationals
including Rúben Neves, Héctor Herrera and Yacine Brahimi to make an impressive 14-minute cameo at the Estádio do Dragão.
It followed a breakthrough season at Under-23s level with manager Steve Beaglehole recommending him to the first-team coaching staff ahead of the trip to Portugal on the back of a string of fine displays. Since then, Barnes has linked up with former City defender Robbie Neilson, joining MK Dons on loan.
The Countesthorpe-based middle man scored on his Sky Bet League 1 debut
to help the Dons secure a thrilling 5-3 victory over local rivals Northampton Town and Barnes has gone on to cement his place in Neilson’s line-up, taking his appearances tally into double figures this month.
Speaking to LCFC TV in Buckinghamshire last week, ahead of the visit of Rochdale, Neilson revealed that he has been delighted with Barnes's impact at Milton Keynes: “His attitude has been great. I spoke to Steve Beaglehole, who spoke very highly of him and he’s matched that.
“He scored on his debut and, since then, I’ve been very pleased. One of the key things about young players progressing to the highest level is attitude. So many players in the Under-23s have great ability but it’s their attitude that really takes them to the next level.
“He’s taken to the group and the group has taken to him as he shows he can play first-team football at this level quite easily. He carries the ball really well. That was one of the things we looked at when we brought him in.
"This pitch is huge and, in League 1, you’re often playing against defenders who aren’t the most mobile so Harvey has helped us exploit that. To have that at such a young age is great. If he can continue to progress then hopefully he can add to that in the future. He has certainly added to this team.”
Barnes, too, has been buoyed by his loan spell in League 1 and says it has been a rewarding experience for him to play against professional opposition on a weekly basis. Both staff and fans alike have commended the City Academy scholar on the ease with which he has adapted to life in the Football League.
Speaking after the 2-2 draw with Rochdale, Barnes admitted that his short stay at MK Dons has been a "really good test" and says he hopes to continue his recent exploits until the end of the season with Neilson's men looking to consolidate in mid-table after a tough start to the campaign under the previous management.
“I’m really enjoying it, I’m getting a lot of experience and it’s bringing me on as a player really well,” he said. “It’s a different situation to what I’ve been in before because there’s a lot more at stake but’s it’s been a good test.
"It’s been really good, the team has been really welcoming to me, they’re a really good group of lads. I’ve been told that the fans have taken a liking to me, too, so that’s really good as well.”
Following his debut strike against Northampton, Barnes found the net again the following week
away at Peterborough United (pictured, above)
but there is some debate about whether he got the final touch on a winning strike against Shrewsbury Town later on in the season.
Barnes added: “I think it’s three goals! But it’s good to get a few goals so that’s really good. It’s a lot different when there’s a crowd here. When things aren’t going right, they’re there to get you over the line. I hope to continue making consistent performance and hopefully grab a few more goals and assists.”
You can follow Harvey's progress at MK Dons - alongside updates on Matty James, Tom Lawrence and Callum Elder - with our weekly loan round-up on LCFC.com.