Newcastle’s nightmare week has finished in heartbreak as the Warriors snatched a dramatic 20-15 win after the final siren to all but end the Knights’ finals hopes.

Already struggling on the field, the Knights spent the week contending with headlines off it, with reports claiming Adam O’Brien would likely be fired as coach after the season and that superstar Kalyn Ponga could follow him out the door.

On top of that, gastro swept through the club and meant only a handful of players were able to participate in the final training session ahead of Sunday’s home game.

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“We had 12 of them in bed over the last 24 hours,” said O’Brien.

“It was a busy morning on the phone to docs and staff running around trying to get medicine and food, trying to get some guys to eat.

“The vast majority didn’t even get to eat before kick-off, they just couldn’t hold anything in. We chopped and changed, I think I wrote the team sheet out about four times this morning.”

But with five minutes to play, halfback Jack Cogger landed a field goal from 37 metres out that just made it over the crossbar and put the Knights ahead by a point.

Stand-in halfback Tanah Boyd then missed a penalty goal that could have won the Warriors the game, awarded when Jackson Hastings was ruled not square at marker after Boyd’s second unsuccessful attempt at field goal.

The Knights’ home crowd rejoiced at Boyd’s miss from the kicking tee, which appeared to have put their team on course for an emotional win.

But as Boyd lined up for a third attempt at field goal, Hastings charged the ball down, only for it to bounce into the hands of Warriors forward Leka Halasima, who ran 45 metres to score the match-winning try.

O’Brien said the Knights nevertheless did their city proud with their effort.

“The town would be proud of them,” he said.

“I’d love nothing more for our staff, these players first and foremost, but for all those people that turn up and chant that Newcastle chant, I’d love for them to win tonight.

“A smile on all their faces would’ve capped off a pretty shitty week.”

The Knights could have wrapped the game up by half-time.

Newcastle led 12-6 at the break after targeting Warriors veteran Kurt Capewell defending at right centre, but could’ve been further ahead had Dane Gagai landed any of three attempts at goal.

The Knights also bombed three first-half tries, first when Greg Marzhew spilt a ball from a Gagai pass, then when Fletcher Hunt and Cogger opted not to pass to unmarked men at close range.

“There’s some stuff there that we have to own,” said O’Brien.

“They proved costly, the ones we bombed.”

The Warriors drew level when Demitric Vaimauga got onto the outside of Jermaine McEwen for a try at close range in the second half, before fellow forward Halasima sealed the win.

“I’ll take it. We’ve been on the end of a few of those in our time,” said Warriors coach Andrew Webster.

“I’m just happy for the boys. It wasn’t pretty tonight but I still felt like we wanted to try and earn the victory and go after it.

“We just came up with a freakish play by a young guy who’s got heaps of talent and that’s what he’s got in his toolkit.”

Defeat left the Knights’ already slim finals hopes in tatters, with the side four victories behind eighth spot and unable to finish the season with a winning record.

The Warriors, meanwhile, have consolidated the top-four position that had appeared under threat from resurgent Brisbane and Penrith.