GOLD Coast fears running defender Lachie Weller has ruptured the anterior cruciate ligament in his right knee.

Weller collapsed to the TIO Stadium turf in the fourth quarter of Saturday's 62-point win over North Melbourne, immediately thumping the ground in frustration.

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When asked post-match whether the Suns thought it was the dreaded ACL, coach Stuart Dew was glum.

"Yeah, that's what the fear is and what it looked like," Dew said.

"We'll find out for sure, but it doesn't look good.

"They never look good when they're in open space and try to change direction.

"We're going to miss him. He's in the form of his career and he's had a real impact on the footy club."

Weller was having another fine game before the injury hit, gathering 20 disposals and using his penetrating right boot to gain a game-high 802m in the hot and greasy conditions.

Dew credited the 26-year-old, along with former No.1 draft pick Matt Rowell, for helping to keep Gold Coast afloat when they were being badly outplayed in the first quarter.

Rowell finished with 25 disposals, nine clearances and 11 tackles to help pilot the Suns to a fourth win in five matches and have them on the cusp of the top eight.

Following back-to-back wins during their 10-day stay in Darwin, Dew said he'd be more than happy to return to the Top End in the future.

"We came to Darwin to get to eight points, and we've got them," he said.

"I feel like we've clawed our way back from two and five, we've squared the ledger and we get to take a break and look forward to the second half of the year."

North Melbourne coach David Noble was again left to lament his team's lack of response after its 17-point quarter-time lead evaporated into a 10th consecutive loss.

He said the glimpses of promise were there, but it just wasn't enough.

"That's the frustrating level. It's there, we know we've got more in us, but we don't deliver," Noble said.

"That's the game. Teams challenge you and you've got to be able to respond."

Despite some of his own team's deficiencies, particularly defensive 50 stoppage work in the game-shaping second quarter, Noble was full of praise for Gold Coast.

"Their defence has been on-point. Their front-half possession game is right in the top four," he said.

"Teams shouldn't underestimate what Gold Coast are doing at the moment.

"They're playing really well. They're defending the ground really well."