Newcastle coach Nathan Brown says changes to key positions and not enough depth were main reasons behind the team's inconsistent form when starting a half of a game in 2018.

As revealed by NRL.com, in the 20 minutes straight after half-time, the Knights have a differential of -69 points, while in the opening 20 minutes of the game they are -66 for the season.

They are the two lowest quarters for any team this season, meaning the Newcastle have conceded the most points during those time frames, according to NRL.com Stats.

Brown said they had started the year much better during those quarters, but he has noticed the trend which has crept into their game in recent months.

"We've probably been a mixed bag but earlier in the year we definitely started the games better than we have of late," Brown said.

"But probably changes to key positions haven't helped, and our depth has probably been shown up at times as well - better sides have strong benches.

"We've probably fallen short at times, but with Daniel [Saifiti] back now and Herman [Ese'ese] playing, and JB [Jamie Buhrer] back playing we certainly got experience so hopefully we can use the bench a bit smarter.

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"Hopefully we can start games well and come out after half-time and play good."

Defence will be the key this Saturday when the Knights host the Titans, with both clubs the only teams to have conceded more than 400 points throughout the opening 18 rounds.

The Titans' third-quarter differential is the fourth-worst in the competition with -58.

Forward Lachlan Fitzgibbon says it's an important game to erase the memories of one of the more painful losses this year, when Newcastle went down 33-26 in round 11.

"We had control for most of that game, but a couple of lapses in the last 10 minutes allowed them to come home with a wet sail," Fitzgibbon said.

"We have seven games left and our goal is to win as many as we can, but it's whatever happens in the eight with teams above us.

"So our focus is to just win as many games as we can and make a little run towards the semis and if it happens, it happens."

Newcastle have confirmed they will not be rushing Kalyn Ponga back from a hamstring injury, naming Nick Meaney at fullback for the second week in a row.

The Maroons debutant was initially given an outside chance to return this week, but Brown said he was too important to risk.

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"He ran pretty well today, but we want him to have a full week of training before he plays," Brown said.

"If he can't do a full week of training next week, he may need to give him a miss [for the Cowboys game].

"But they were confident when it happened that he would be back in the three-week range."