With the play-offs finally kicking off after 15 rounds, the club's reserves booked a grand final berth following their gutsy - and nail-biting - 16-10 victory over minor premiers Scone Thoroughbreds at Scone Park on Sunday.

Twenty-four hours earlier, at Singleton's Pirtek Park, the Magpies' league tag squad eliminated the Muswellbrook Ramettes 28-4 from the title race.

Merriwa now faces Murrurundi in the preliminary final after the Mavettes suffered a 24-6 loss to the Thoroughbreds.

The winner tackles Scone in the 2019 decider.

The Thoroughbreds also tasted success in first grade, defeating the Aberdeen Tigers 30-16, while the Singleton Greyhounds upset the Muswellbrook Rams 42-10 in under-18s.

Meanwhile, in the other fixtures on Saturday, the minor semis, Singleton knocked out the Denman Devils 38-4 in the main encounter.

Reserve grade saw the Tigers jettison the Rams 34-14, while their under-18s proved too strong for the Thoroughbreds 26-12.

The preliminary finals will be played at McKinnon Field, Aberdeen, on August 31.

Minor semi-finals -

(Saturday - Pirtek Park, Singleton)

First grade: Singleton Greyhounds d Denman Devils 38-4

Reserve grade: Aberdeen Tigers d Muswellbrook Rams 34-14

Under-18s: Aberdeen Tigers d Scone Thoroughbreds 26-12

League tag: Merriwa Magpies d Muswellbrook Ramettes 28-4

Major semi-finals

(Sunday - Scone Park, Scone)

First grade: Scone Thoroughbreds d Aberdeen Tigers 30-16

Reserve grade: Merriwa Magpies d Scone Thoroughbreds 16-10

Under-18s: Singleton Greyhounds d Muswellbrook Rams 42-10

League tag: Scone Thoroughbreds d Murrurundi Mavettes 24-6