The points looked as though they would be shared on Merseyside after a tight encounter, only for Barrington to rifle home a right-footed effort into the top corner to seal the points for Ben Wilkinson's side.
It was a slow start to proceedings on Merseyside with both sides struggling to find a way past each other's high pressing defences.
Whilst there was plenty of action around both boxes, not many clear-cut chances were created until the 15th minute when Oakley Cannonier diverted home Melkamu Frauendorf's shot, only for the linesman's flag to be raised for offside.
Liverpool's Bobby Clark, in particular, was looking dangerous down the left hand side, but City central defenders Shea Charles and Jadel Katongo did well to nullify his threat, cutting out most of his crosses before they could reach the Reds' strikers.
As we reached the latter stages of the half, City grew into the game and chances started to arrive, the most dangerous of which being Carlos Borges' cross falling just beyond the outstretched leg of Will Dickson with the goal gaping.
Following the break, we started lively as half-time substitute Micah Hamilton burst into the box and could've got a shot away had it not been for good reactions from Liverpool keeper Harvey Davies to claw it away.
Josh Adam also came close to finding an opener when he let fly from the edge of the area, only for his shot to be tipped over by Davies.
Up the other end, Liverpool had a great chance to score in the latter stages, as full back Josh Davidson produced a mazy run before threading a pass towards substitute Harvey Blair, but it drifted just beyond the attacker as City were let off the hook.
And we took full-advantage as in the 86th minute, substitutes Dan Ogwuru and Barrington combined, the former playing through winger Barrington who fired a right-footed shot into the top left-hand corner, sealing the win for the Young Blues.
HOW WE LINED UP
WHAT IT MEANS
The two sides came into this game split by just two points, with City second in the U18 Premier League North Division table and the Reds third.
Thanks to that late winner from Barrington, we now increase our advantage over Liverpool to five points.
City remain second, two points adrift of leaders Blackburn Rovers, who won convincingly away at Leeds United on Saturday.
Our U18s are next in action on Tuesday night as we face Brighton and Hove Albion in the fourth round of the FA Youth Cup.
The next time we will be in league action will be Saturday 22 January as we face Stoke City at the City Football Academy. Kick off is at 12:00 (UK).
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