The Penrith Panthers have confirmed the immediate retirement of Matthew Eisenhuth.

The forward, who has been part of the Pantherts' squad since 2021, has been a constant fringe player for Ivan Cleary, but is regarded by those around the club as the ultimate teammate.

Eisenhuth, who actually captained the Panthers in his final NRL appearance, played 75 games for the club at the top level, while also spending plenty of time in reserve grade mentoring other young forwards.

Prior to that, the one-time Prime Minister's XIII representative also played 70 games for the Wests Tigers between 2017 and 2020, taking his career tally in the top grade to 145.

Concussion related issues have hampered him in recent times though, and he will not add to the total.

Penrith rugby league CEO Matt Cameron recognised Eisenhuth's enormous contribution to the club and sport.

“I had the pleasure of coaching Matt as a young NYC player, and to see him finish his career representing the Australian PM's XIII against Papua New Guinea was incredibly special,” Cameron said.

“He has been an incredibly valued member of our organisation, and it's been a privilege to watch his transition from a young player into the professional and respected athlete he is today.

“His work ethic, leadership and commitment to the team helped set the standard for those around him, and he played an important role in the success we've enjoyed in recent years.”

The 33-year-old, who was named the 2024 Penrith club person of the year, is expected to move into a coaching or off-field role with the club at the foot of the mountains following his retirement.