Penrith have assumed their now-customary position atop the NRL ladder after putting under-manned Newcastle to the sword 38-20 in Bathurst.

Newcastle led the depleted premiers late in the first half at Carrington Park before a brain explosion from Knights second-rower Mitch Barnett turned Saturday’s top-of-the-table clash on its head.

Barnett was sent off for an off-the-ball elbow to the head of Penrith forward Chris Smith that even had retired hardman Steve Roach shaking his head in disbelief.

Commentating on Fox Sports, the legend said he thought such acts of old-school foul play were a thing of the past and tipped a lengthy suspension for Barnett.

“That’s a bad one. He’ll be sitting on the sidelines for a fair while,” the former Test prop said.

“That’ll be hard to defend, that one.”

With Smith failing a HIA following the ugly incident, Penrith were forced to activate their 18th man and introduce Lindsay Smith for the duration of the match.

The premiers were already missing more than half their 2021 grand final-winning line-up after James Fisher-Harris (shoulder), Liam Martin (leg) and Brian To’o (knee) joined skipper Nathan Cleary in the casualty ward.

The quartet’s absence followed the off-season departures of Paul Momirovski, Matt Burton, Kurt Capewell and Tyrone May’s sacking.

And, despite Kaylan Ponga’s late withdrawal, the Knights threatened an upset when they led the baby Panthers 6-4 until the 33rd minute.

But, Barnett’s marching orders sparked a point-scoring blitz from Penrith.

Stephen Crichton levelled the scores from the ensuing penalty before Taylan May, proving worthy cover for To’o, grabbed his second try of the afternoon in the shadows of halftime to give Penrith the lead.

Izack Tago’s second-half double and further tries to Crichton, Charlie Stains and May’s third three minutes from fulltime extended the Panthers’ unbeaten start to 2022 and consigned Newcastle to their first defeat of the season.

Penrith returns home to BlueBet Stadium to host South Sydney in a grand final rematch on Friday night, while Newcastle will look to rebound against Cronulla in round four.  

The Knights also have judiciary concerns over Chris Randall and Jacob Saifiti after they were placed on report for crusher tackles on Saturday.

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