South Sydney will have to do without their captain Cameron Murray for the remainder of the season after he failed to downgrade a charge at the NRL Judiciary earlier in the week.
The forward was issued with an initial two-match suspension for his high shot on Tyson Frizell but opted to challenge the findings in the hopes of escaping the sanction.
Instead, Murray copped a three-game ban which means he will miss his side's clash with Penrith in Round 26 as well as their final match of the season against the Sydney Roosters.
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Rabbitohs name replacement for suspended Cameron Murray ahead of Panthers clash
When team lists dropped this week, Ben Hornby named Murray at lock for the battle against the Panthers.
Although he has now been ruled out of the contest, with the Rabbitohs forced to shuffle their pack in order to accommodate for the absence of the skipper.
"Keaon (Koloamatangi) will go back to lock and Liam Le Blanc will come onto the bench," the interim coach revealed.
Koloamatangi has operated at lock for a large chunk of the Bunnies' season so far, playing 10 games in Murray's customary position.
The Tongan international first appeared in the No.13 jersey in Round 12 against Parramatta, with the Bunnies emerging 42-26 winners.
This kickstarted a golden run for the club as they won five of their next six games with Koloamatangi at lock.
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However, after three straight defeats against Canberra, Cronulla and Melbourne, Murray was re-instated through the middle with Koloamatangi reverting to an edge.
Koloamatangi has been a rare bright spot for the Bunnies after a slow start to the season, which saw him way down on his usual standards and overlooked for New South Wales selection in State of Origin.
The 26-year-old managed to turn things around on a personal level though following the positional switch.
He has averaged 163 run metres per game while boasting a 93.5 per cent tackle efficiency during a lean period for the club.
