There was widespread interest in this game with the first-team contingent of both teams in attendance at the 7,000-capacity Joie Stadium.
United’s manager in waiting Michael Carrick took his seat in the stands alongside his coaches, as well as captain Bruno Fernandes, Mason Mount, Luke Shaw and Patrick Dorgu.
But it was the City youngsters and the supporters along with first-team boss Pep Guardiola and senior players such as Phil Foden, Antoine Semenyo and Nathan Ake who were celebrating as the U18s lifted the trophy.
The pre-match star billings of Teddie Lamb and JJ Gabriel, who have scored a combined 54 goals between them this season, were both kept quiet for large periods of the contest.
City’s prolific striker Lamb’s close-range effort was kept out by Byrne-Hughes’ incredible reflex save and he also somehow scooped an effort over the crossbar from inside the six yard box.
At the other end, the Premier League U18 player of the season Gabriel did call Max Hudson into making a comfortable save low down, while the 15-year-old was also booked for simulation in the box.
Chido Obi, who had screwed wide from a promising position, then saw a better opportunity fall his way 14-yards out in the centre of goal, but City captain Kaden Braithwaite made a brilliant sliding challenge to deny the United striker.
After trading first-half goals, City felt they had a good shout for a penalty when Byrne-Hughes appeared to bring down Samba in the box, but the hosts were awarded only a corner, much to their displeasure.
Reiss’ side were creating the better chances and Heskey gave a warning sign when he struck into the side-netting, before belting home the winning goal which he will remember for the rest of his career.