New Zealand Warriors coach Brian McClennan has branded his side's 52-12 defeat by the North Queensland Cowboys as their darkest hour this season.

The Cowboys secured their biggest win over the Warriors in Townsville on Saturday, scoring nine tries and handing the visitors their fifth consecutive loss.

The result means that the Warriors effectively have no chance of reaching the top eight this season, only a year after appearing in the club's second NRL grand final.

The weekend before, the Warriors went down 45-4 to the Sharks, but McClennan said the Cowboys defeat was a new low.

"Everybody is devastated as you could imagine," McClennan said.

"There's not a lot that you can really say."

The Cowboys dominated throughout, with star standoff Jonathan Thurston running riot against a rudderless Warriors side who struggled to fire on attack and leaked more tries in a single match than they have all season.

Although the hosts scored four tries in the first 20 minutes, McClennan said his side were confident at halftime that they could claw their way back into the match.

"At halftime, we thought we finished well and we had a bit of hope that we could string some good sets together," the former Kiwis coach said.

"[But] we went out and handed it over straight away. They scored and it just snowballed from there."

While the Warriors' 15 errors and 49 missed tackles were glaring statistics, the worst perhaps was the side's completion rate, which sat at 53 per cent as they finished just 16 of their 30 sets.

"That's a really bad completion rate, which we've done in the last two games," McClennan said. "The thing is in a lot of games before that we were completing 30-plus sets. The last couple of weeks we've been really poor there.

"A lot of that's to do with we've got behind early. We end up trying to chase, and you've just got back into a grind. We just weren't able to do that."

Although standoff James Maloney was a late inclusion, the Warriors had to do without Elijah Taylor, who flew back to Auckland the night before the match after learning his father, Ron, had died.

McClennan described Taylor's team-mates as feeling "devastated" for the promising back rower.

"We quickly got him back to be with his family," he said. "Elijah's dad had been ill for a while but he'd taken a turn.

"It's very sad. Elijah is a 22-year-old young man, and you deserve to be with your father for a lot longer than that."

Fullback Kevin Locke limped out of the match with a sprained ankle during the first half.

McClennan said Locke would undergo scans early this week to determine whether he would be fit enough to play against the Panthers on Sunday.

- © Fairfax NZ News