Newcastle Knights coach Adam O'Brien rues another close loss to depleted Penrith Panthers

After his side's third consecutive loss on Saturday night, outclassed by a largely second-string Penrith side 20-12 at BlueBet Stadium, O'Brien said there was no simple solution to his side's woes other than hard work and perseverance.

"If there was an easy fix, I certainly would have fixed it," he said.

"Some weeks we're coming up short with the ball, and I felt like tonight we lacked going to a plan B.

"We just kept throwing the same sort of shift and shape at them, and they handled it.

"Being able to transition into a different style, or jump off script a bit, is certainly an area where we can improve. But in saying that, out attack has been fairly good this year.

"There is no one thing.

"It seems to be we plug a hole there, and another leak sprouts the next week.

"We've just got to keep looking at our game and how we can improve it."

Penrith were without injured halfback Nathan Cleary, and rested NSW representatives Jarome Luai, Stephen Crichton, Liam Martin, Isaah Yeo and Brian To'o, but still the Knights couldn't get the job done.

The home side didn't miss a beat in front of 18,589 fans at their fortress ground, where they've now won 31 of their past 34 NRL games.

Steered by former Knights playmaker Jack Cogger in Cleary's absence, Penrith jumped to a 16-6 lead by half-time and never really looked in doubt in the second half despite Knights halfback Jackson Hastings' 54th-minute try which reduced the deficit to only eight points.

"They were just relentless at what they do," Knights skipper Kalyn Ponga said.

"Turned people under, kicked well. Just play a simple game and do it for 80 minutes. They controlled that second half, it was hard for us to get out of our own end."

Penrith didn't make a mistake in the first half and finished with a 90 per cent completion rate.

Newcastle's was just 62.

"We shot ourselves in the foot a little bit with some execution, and we got a little bit panicky," O'Brien said.

"The opposition, I thought they were very professional tonight ... they were never going to beat themselves."

The loss, Newcastle's ninth in 15 games this season, leaves them languishing in 14^th position, at least three wins outside the top eight.

They have nine games remaining, but will likely need to win the vast majority to be a chance of making the finals.

Their next two are against lowly Canterbury and Wests Tigers, split with another bye.

Saturday's game was the sixth Newcastle have lost by eight points or less this year.

"There's a ton of effort gone in," O'Brien said.

"The boys are certainly in there swinging away with a ton of effort. We're just lacking a little bit. We need to stick together, stay tight and try and make it turn."

O'Brien was disappointed to lose interchange prop Jack Hetherington to the sin-bin late in the first half for slapping Izack Tago, but he questioned why the Penrith centre wasn't similarly punished.

"I could clearly see [Jack] got slapped from the ground," he said.

"That one was hidden, Jack's wasn't. Jack's was pretty blatant.

"In the end, it wasn't a smart thing to do by Jack. I think he would be the first one to admit that.

"If you're getting 10 minutes for striking in the face, I can clearly see him getting struck from the ground up - it's still a strike on the face."

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