Full back Ben McFarlane was the hero for the Malone Road school landing a long-range penalty in the dying minutes to secure the victory.
Campbell made the prefect start when Methody went off their feet at the breakdown on their own 22 allowing winger Peter Caves to slot over a second minute penalty.
Methody replied immediately after Campbell failed to deal with the restart.
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From a scrum Methody went to their one out runners coming hard around the corner, eventually Campbell ran out of numbers and powerful centre Lorcan Hanratty barged over from close range with McFarlane converting.
Campbell were denied a try on 23 minutes, they kicked a penalty to the corner, from the lineout instead of going for the driving maul the boys in black made a sniping break down the blindside after prop Darragh Hanlon released hooker Zac Solomon.
The hooker got to the try line, but Methody had enough covering defenders to knock the front rower into touch and get a clearing drop out kick.
Campbell regained the lead on 33 minutes. Lock Joe Hopes took a crash ball at pace and charged through the Methody defence from the 10-metre line.
He was stopped close to the try line, scrum half Johnny McCracken hit Solomons and this time the hooker wasn’t to be denied as he dummied before going over.
Caves conversion gave Campbell a 10-7 lead at the interval.
Campbell scored their second try three minutes after the restart.
Out-half Tom Crowther launched a penalty into touch in the Methody 22, from the line out the Campbell’s forwards set up a driving maul, McCracken looked to go to the blindside but changed direction hitting winger Oliver Topping coming onto the ball at pace and he galloped over with Caves adding the extras.
Methody should have replied when after some probing carries the ball was spun wide and winger Chris Bradley raced for the try line, but Campbell full back Lukas Kelly showed great speed to make up the ground and made a last-ditch tackle.
However, Methody did reduce the deficit with a try on 47 minutes.
From a scrum in the Campbell 22, No 8 Michael Crothers made a powerful surge from the base, the forwards had a couple more probes at the line before lock Harry Palmer forced his way over with McFarlane knocking over the conversion.
Campbell’s defence held firm as Methody were in the shadow of their posts looking for the go ahead score but McCracken was able to win the turnover and force a penalty.
McFarlane levelled the scores with eight minutes remaining with a sweetly struck penalty.
And he landed a monster kick from 45 metres with only two and half minutes on the clock to give Methody a three-point lead after Campbell were adjudged to have played the ball on the ground
Topping made a huge break down the right wing entering the Methody 22 before being dumped in the dying second.
Campbell moved the ball from east to west, but Methody were able to scramble their defence and bungle the ball carrier into touch to seal the game.