Johnstone polled 27 votes to take the award, edging out teammate Paige Wade and Deni Rams’ Leah Blake, each with 24 votes.
Johnstone and Wade are key pieces in the Blues’ undefeated B-grade side, which is set to take on Moama in the grand final this Saturday.
Several other Blues came close to claiming best-and-fairest honours, with Tracey Hughes runner-up in C-grade and Sam Tyler tied for runner-up in reserves football.
Moama’s Jack Russell and Cobram’s Samuel Beasley were declared joint winners of the prestigious O’Dwyer Medal for the best-and-fairest senior footballer.
For the first time since 2017, a Magpie received the seniors’ top honour, co-sharing it with a Tiger. Beasley is the first Tiger to win the O’Dwyer Medal since 2011.
Russell and Beasley, who captain each of their sides, received 22 votes apiece, while runner-up Jack Norman polled 19 votes to narrowly miss out on the honour.
Rumbalara’s Jessie Barnes-Hill stood peerless as the clear-cut best-and-fairest winner in A-grade netball.
Barnes-Hill received 42 votes, due to her major role in Rumba’s dominance in the 2024 season, which led it to a chance at the flag in Saturday’s grand final against Moama.
The runner-up was Deniliquin Rams coach Rhiannan Maxwell, who tallied 28 votes.
Congupna’s Kyle Mueller took home the Les Mogg Cup for the seniors’ leading goal-kicker, nailing an impressive 95 majors in the 2024 season.
Nathalia’s Kai Lundberg received the league’s rising star award in 2024, kicking 12 goals in 17 appearances and finding himself on his side’s best list 12 times.
Numurkah’s Jordan O’Dwyer received the Eagle I most valuable player award, as voted by the league’s clubs.
Tongala at the Murray League presentation night
Best-and-fairest:
B-grade netball: Sienna Johnstone
B-grade joint runner-up: Paige Wade
C-grade runner-up: Tracey Hughes
Reserves runner-up: Sam Tyler