City had to come from behind after Kamari Doyle’s curling strike put the hosts ahead.
Two goals in just over 10 minutes turned the game around, as Tai Sodje and Dire Mebude slotted home to give us the lead before the break.
And no further goal action in the second half meant we celebrated winning our third successive National title.
Buoyed by the home support of 13,035, it was the Saints that started with the most energy, catching us in possession in the early stages.
It was Sodje who had the first chance for City when the ball came to him rapidly from Nico O’Reilly in the box, but he could only slice his shot high and wide of the goal.
Southampton responded quickly at the other end, as Kamari Doyle dribbled round Rico Lewis before answering a shout from the crowd for him to shoot, but his weak effort rolled into Josh McNamara’s gloves.
However, the hosts took the lead when they latched on a pass out from the back by McNamara.
The ball eventually found Doyle, whose low effort shot curled past the City keeper to the home crowd’s delight.
But the equaliser arrived soon after when Mebude put on the burners to reach a through ball before finding Sodje at the near-post, with the forward tapping home.
We didn’t look back after our goal, with a pinpoint ball by Carlos Borges finding Mebude on the right, who ran at the Saints defence before picking his spot and slotting past Eddie Beach to turn our fortunes around on the south coast.
Southampton came out to the second half with renewed confidence sourced from the home support.
However, it left areas for us to expose and a flowing move down the left was switched to the right flank by Borges for Mebude to set up O’Reilly, but there wasn't enough power in his shot.
City had to hold firm as the Saints were not giving up. Substitute Jimmy Jay Morgan had an effort deflect agonisingly around the post before Doyle, who proved to be a constant thorn in our side, struck straight at McNamara.
But the Young Blues were professional and strong, and secured us a credible award for what has been a fine season.
WHAT IT MEANS
City were crowned Under-18 Premier League National champions.
This follows an incredible campaign by Ben Wilkinson and his young side having already been awarded the Under-18 Premier League North title.
HOW WE LINED UP
Ben Wilkinson selected a strong line up for the Under-18s Premier League Final.
Starting XI: Beach; Davies, Pambou, Payne, Hewlett (C), Finnigan, Edwards, Bragg, Pearce, Doyle, Carson
Subs: Wright, Hall, Tshaka, Dibling, Morgan
Manchester City Under-18s
Starting XI: McNamara; Lewis (C), Alleyne, Katongo, Galvez, Breckin, Charles, O’Reilly, Borges, Sodje, Mebude
Subs: Murray-Jones; I Smith, Adam, Dickson, Barrington
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