A charge-down try with less than two minutes remaining proved the difference as The Hills Sports High School lost a thrilling NRL Schoolboys Cup grand final to Patrician Brothers Fairfield.

Patrician Brothers stormed home from a 16-0 deficit to claim Australia’s premier secondary schools’ rugby league competition 20-16 at Leichhardt Oval.

Player of the match Joshua Alhazim scored the clincher as the clock ticked past 58 minutes, charging down a kick and scooping up the ball to dot down near the posts.

The Cup had very much looked there for the taking for Hills who racked up a 10-0 lead in the first half courtesy of tries to Alaa Lababidi and Blake Metcalfe.

And the school seemed to have one hand on the prize when Jonathan Ibrahim scored a converted try shortly after the break to make it 16-0.

But Patrician Brothers refused to yield and scored three tries of their own to make it a two-point ball game as the clock wound down, before the heartbreaking final instalment.

"We put ourselves in a position to get a result but we just couldn't finish it off," said The Hills Sports High School Director of Sport Andrew Tetley.

Hills had been contesting a third title after it beat Canberra’s Erindale College in a golden-point thriller to secure a place in the decider.

The school’s ongoing success is attributed to its Talented Sports Program, which provides specialised support to its elite athletes.

“We have a mission statement: we want to support and nurture young men to be the best possible people they can be, using rugby league as the vehicle for that,” coach Scott Jones said.

Despite the loss, Hills Sports High School's season isn't quite over - with a semi-final of the University Shield to be played against Westfields Sports High next week and then potentially a grand final.