The first domino in the Penrith Panthers' upcoming contract battle is set to fall, with the club resigned to losing Brian To'o at the end of 2027.

Zero Tackle understands per sources linked to the winger that the representative star and his camp will not be re-signing with the Panthers beyond the end of 2027.

To'o will be allowed to formally negotiate with rival clubs from November 1 given he is off-contract at the end of 2027, however, it's believed the PNG Chiefs are his preferred landing spot.

That hardly comes as a surprise given the Port Moresby-based club who join the competition in 2028 have already signed one of his best mates in Jarome Luai, who will exit the Wests Tigers at the end of 2027.

Luai is joined at the Chiefs by South Sydney Rabbitohs winger and the game's greatest ever try-scorer Alex Johnston, while Zero Tackle also understands Connor Watson is likely to be player number three, spending a year at the St George Illawarra Dragons in 2027 before making the move north.

Zero Tackle reached out to the Panthers and were told he is contracted until the end of 2027, and that the club have no official comment to make on the matter.

Brian To'o's management have also been contacted, but no response was received at the time of publishing.

The news, which has been brewing for a number of weeks, comes hot on the heels of coach Ivan Cleary confirming he will step down from head coaching at the end of 2027, although will remain linked with the club in an advisory role.

The men from the foot of the mountains face an enormous contract squeeze at the end of 2027, with To'o joined by Paul Alamoti, Nathan Cleary, Sione Fonua, Mitch Kenny, Moses Leota, Liam Martin, Isaiah Papali'i, Luron Patea, Billy Scott, Blaize Talagi and Isaah Yeo as the players coming off-contract.

Penrith also have Tom Ale, Jack Cole, Kalani Going, Thomas Jenkins and Freddy Lussick off-contract at the end of 2026, with Jenkins the most likely of that group to leave.

Of the players off-contract at the end of 2027, it's believed Mitch Kenny and Liam Martin have entertained the idea of a PNG move, with the Chiefs set to raid the foot of the mountains, while both Nathan Cleary and Isaah Yeo have indiciated they could test the open market from November 1.

It sets the scene for a high stakes contract war for the Panthers ahead who will have to shake some talent in order to comply with the NRL salary cap.

They will likely make Nathan Cleary their priority retention, but exactly what they will have to pay the New South Wales Blues halfback remains to be seen, with competing interests both professionally and personally for Cleary given the Chiefs and other clubs will come in hot, and the fact his partner soccer player Mary Fowler lives in the United Kingdom.

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To'o, who is believed to be on around $625,000 per year at the foot of the mountains, will also be in for a major contract upgrade as he signs his next deal, although should he land in PNG, tax free money will certainly be a selling point.

The 27-year-old has scored 95 NRL tries in 144 games since making his debut for the Panthers, while he has also scored 11 in 15 matches for the NSW Blues, and 6 in 11 matches for Samoa at international level.

He will be an almost certain starter for Samoa at the end of year Rugby League World Cup, and has been named on the wing for the NSW Blues ahead of Game 1 of this year's State of Origin series, to be played next Wednesday night in Sydney.