The striker scored the opening goal in a 2-1 win to become the third youngest post-war goalscorer in the Club’s history at the age of 17 years and 229 days.
“To take my opportunity and score and help us into the next round, I couldn't be happier,” he said after his milestone moment, which puts him on good company amongst City's teenage scorers.
Here, we take a look at other notable players to have hit the back of the net at the same age…
The youngest goalscorer in City’s history got off the mark just eight days after his 17th birthday, when he slotted the third goal in a 3-0 FA Cup win over Watford in January 2013.
Like Delap, the Portugal forward had the honour of opening his account on his debut, firing into the bottom corner from the rebound of Mario Balotelli’s saved effort.
And the magnitude of it all almost rendered Lopes speechless.
“In my first game for the first team to get my first goal; I have no words to explain my feelings,” he said during his post-match interview.
The following January, the man nicknamed Rony starred in the 3-0 win over West Ham in the League Cup semi-final second leg, where he provided two assists.
He joined Lille on loan for the 2014/15 season, before signing for Monaco in August 2015.
Before Lopes, it was Bury-born Ian Thompstone who had the honour of being our youngest post-war goalscorer.
The midfielder struck aged 17 years and 83 days in a 2-1 defeat to Middlesbrough in 1988 on what proved to be his one and only appearance for the Club.
“I was dead excited, and the goal came from my second touch of the ball,” he said in 2013.
“A cross came in, I headed it into the box and Gary Pallister tried to clear but knocked it back out to me. I just hit it and couldn’t believe it when it went in.”
Thompstone played in our 1989 FA Youth Cup final defeat to Watford, before an ankle injury left him out for nine months.
He joined Oldham in 1990 before spells at Exeter City, Halifax Town, Scunthorpe United and Rochdale.
Micah Richards propelled himself into the limelight with a powerful header in a 1-1 draw with Aston Villa in the FA Cup.
The Premier League winner was 17 years, 7 months and 26 days when he netted his first goal for the Club in the dying seconds at Villa Park.
Goalkeeper David James had ventured forward in a last-ditch attempt to rescue the tie, but it was the young right-back who met Joey Barton’s corner emphatically, before racing to celebrate with the City fans.
And of course, we can't reference this particular goal, without mentioning the famous post-match interview which followed!
Fallowfield lad Neil Young scored 108 goals in 415 games for City and he made a flying start to life in the first team whilst still only 17.
He got up and running with his first goal a month after his debut, netting in a 3-0 home win over Ipswich Town in December 1961 at 17 years, 10 months and six days.
Blessed with a powerful yet cultured left foot, Young, made a seamless transition into senior football, netting 10 goals in 24 league games during his debut campaign.
A City legend in every sense of the word, Glyn Pardoe remains our youngest ever player at 15 years and 341 days old.
The full-back, who sadly passed away in May, scored his first goal in a 2-0 win over Huddersfield Town in April 1964 when he was still only 17 years and 315 days.
At that stage of his career, the grandad of Tommy Doyle was playing in a more advanced role, before moving back to left-back, where he truly excelled.
Tony Towers enjoyed some particularly memorable moments whilst wearing a City shirt during his teenage years.
Handed his debut just six days after his 17th birthday in an April 1969 defeat at Southampton, he went on to force his way into the side the following season.
One month shy of turning 18, Towers came off the bench to score an extra time winner over Portuguese outfit Academica Coimbra in the European Cup Winners Cup quarter-final and started in the final as we beat Górnik Zabrze to lift the trophy.
He went on to play more than 150 games for City, was capped three times by England and also represented Sunderland and Birmingham City before a spell in the United States.
A first goal is a memorable occasion in any players career, but confusion reigned when Taylor Harwood-Bellis was on target against Port Vale in January 2020.
The young centre-half scored in slightly fortuitous circumstances 26 days shy of his 18th birthday, but initially there were question marks as to whether it was his goal and, if so, whether it would stand.
A VAR decision to check whether he was onside made for some subdued celebrations from the Academy graduate.
“I didn’t quite know how to react to scoring as I’ve not been in a game with VAR before,” he explained afterwards.
“But a couple of Port Vale players said I could be onside, so I got my hopes up and, fortunately, it was given.
“I said to John I was trying to move out of the way and then when it wasn’t offside I said that I meant it!”