NRL: Penrith Panthers book grand final spot after defeating South Sydney Rabbitohs

Nathan Cleary of the Panthers celebrates with Dylan Edwards after scoring a try during the NRL Preliminary Final match. Photo / Getty

The Penrith Panthers hopes of going back-to-back are alive after taking care of business against the South Sydney Rabbitohs on Saturday night.

The Rabbitohs had control of the contest in the early going, but the Panthers put the foot down late in the first half and they never relented as they claimed the 32-12 victory.

All season long the Panthers were the team to beat but they met their match in the opening half, the NRL bunker.

Three tries were taken off the minor premiers with fans left in utter disbelief after one was disallowed due to Jerome Luai gaining an advantage after going behind teammate James Fisher-Harris with the ball in hand.

"That is ruthless. Absolutely ruthless," Dan Ginnane said on Fox.

"Have a look where Kennar is … there's no way, there's got to be common sense here," Steve Roach added.

"It should be a try. There's no way he was going to tackle him there. No way."

Andrew Johns on 9's coverage couldn't believe what he had seen.

"This is … honestly, this is laughable," he said.

"There've been some howlers this year. It's not black and white when a player runs behind (a defender)."

In the final five minutes of the opening half the Panthers crossed twice with Brian To'o pinballing his way through Cody Walker as he levelled things up before the halftime break.

The Panthers kept their foot to the floor from the outset of the second half as they put the Rabbitohs to the sword.

A chase down block from Viliame Kikau set the Panthers on their way before a deft kick from Nathan Cleary dribbled into the end zone as Spencer Leniu went full stretch to get the ball down.

The loss for the Rabbitohs went from bad to worse in the dying stages after Taane Milne was sent packing after delivering a sickening hit on Spencer Leniu.

Izack Tago got on the end of one before Nathan Cleary put the final nail in the coffin with a piece of individual brilliance.

Penrith advance to their third straight Grand Final where they'll face off against the Parramatta Eels who booked their ticket to the Grand Final with a thrilling win against the North Queensland Cowboys on Friday.