Trailing by eight early in the second half, the stage was set for the Panthers to produce a fourth straight dramatic finish in their final home game of the season.

However a 70th-minute try to Ken Sio and his sideline conversion into a fierce wind ended any thought of another fightback.

Penrith's frustrations boiled over in the closing stages, with Viliame Kikau and Tyrone May sin-binned for throwing punches.

Knights pair Danny Levi and Shaun Kenny-Dowall joined them, while a fan was tossed for throwing the match ball at the Newcastle bench after a touch kick landed in the crowd.

Panthers hooker Wayde Egan nabbed a consolation try but it wasn't enough and questions surrounding the team's ability to contend for the premiership are sure to multiply.

The loss for Penrith - caretaker coach Cameron Ciraldo's first since taking over last week - opens the door for St George Illawarra or Cronulla to steal a crucial top-four spot.

The Panthers were disappointing from the outset in front of a strong 14,125 crowd, appearing disjointed in attack without injured veteran James Maloney.

In contrast, the Knights were led by strong performances from their spine, highlighted by a classy effort from Kalyn Ponga in his first appearance at five-eighth.

Fullback Nick Meaney and co-captain Mitchell Pearce also stood tall.

Playing into a fierce southerly in the first half, the Panthers' afternoon went south early.

Tries to Aidan Guerra and Cory Denniss inside the opening 20 minutes gave the Knights an 8-0 advantage and it appeared the Panthers were destined to chase a big lead again.

However a long play-three kick from Nathan Cleary paid off when Corey Harawira-Naera forced an error from Meaney that gave Tyrone May an easy passage to the line.

Australian Associated Press