In what was a high-quality affair, Porto had opened up a two-goal lead at the break.
A 17th minute penalty from Tiago Silva broke the deadlock before a second Porto strike from Mateus Mide on the stroke of half-time doubled the advantage.
Oliver Reiss’s side created several fine chances and also saw Christian Dunbar-McDonald hit the post before substitute Teddie Lamb deservedly halved the deficit on 73 minutes.
However, with City pressing, Porto then struck again seven minutes from time through substitute Tcherno Jamanca to clinch victory.
What happened in brief
The clash marked a first-ever meeting at this level between City and Porto and with the hosts boasting a fine UEFA Youth League record, it promised to be a testing assignment.
That was borne out almost immediately with Porto hitting the bar within a minute through Cardoso Varela after a quickfire attack.
Almost immediately at the other Porto ‘keeper Nikolov had to be alert to deny Floyd Samba’s well-struck shot after the City front man had been put in the clear.
However, it was the hosts who struck first on 17 minutes via a penalty.
The spot-kick had been awarded after Kaden Braithwaite was adjudged to have held Eduardo Ferreira in the box.
And from the resulting spot kick Tiago Silva made no mistake, putting Porto ahead.
It was a tough blow to take but City came within a whisker of drawing level on 24 minutes through Christian Dunbar-McDonald.
The winger embarked on a superb driving run up the left flank before letting fly from just inside the box and it needed a crucial fingertip save from Porto ‘keeper Antonio Nikolov to divert the effort onto the post.
It then needed Chabot to produce a superb diving save at the other end to deny Mateus Mide on 36 minutes after the Porto wide man had cut inside from the left edge of the box and curled in a superb shot.
However, the young Blues suffered a big body blow on the cusp of half-time when Mide struck to double the hosts’ lead.
A long ball over the top saw the Porto forward sneak in behind the City back line and after first rounding Chabot, he then coolly slotted home.
It was tough on Reiss’ side who kept pushing after the break with Xavier Parker amongst those to come close.
And our persistence was rewarded on 73 minutes when substitute Teddie Lamb rifled home his maiden Youth League strike to halve the deficit.
The Blues youngsters strained every sinew in an effort to force an equaliser but it was Porto who struck again to seal victory on 83 minutes.
Seeking to play out from the back City lost possession and from Tiago Silva’s inviting pass, substitute Tcherno Jamanca made no mistake from eight yards out.
How we lined up
Max-Edgar Chabot was in goal and shielded by a back four of Brooklyn Nfonkeu, skipper Kian Noble, Kaden Braithwaite and Marlow Barrett.
Harrison Miles, Finley Gorman and Xavier Parker were in the engine room with Kylan Midwood, Floyd Samba and Christan Dunbar-McDonald deployed upfront.
PORTO: Nikolov, Ferreira (Froholdt 70), Salvador Gomes, Martim Chelnik, Martim Cunha, Granaas (Goncao Oliveira 75), Bernardo Lima, Tiago Silva, Mateus Mide (Muxito 75), Cardoso Varela (Duarte Cunha 60), Eduardo Ferreira (Jamanca 70)
SUBS: Mendes, Rodrigo Teixeira, Jose Domingues, Demirci.
CITY XI: Chabot, Nfonkeu, Noble (C), Braithwaite, Barrett (Houlihan 83), Miles, Midwood (Wain 58), Gorman (Lamb 58), Parker, F. Samba, Dunbar-McDonald (Oliver 66)
SUBS: Vickery, Lawrie, Carrington, Motsi, Woode
What it means
Frustration in our opening league phase match with City yet to get off the mark points wise.
What’s next
City’s next UEFA Youth League tie is at home to Paris Saint-Germain with the tie to be played on Wednesday, October 14.
Kick-off at the Joie Stadium is set for 15.00 (BST).
Our EDS side is back in action next Tuesday, September 15 when we travel to Chesterfield for our second EFL Trophy group clash.
Kick-off is set for 19.00 (UK).
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