'Just horrible': Brutal reaction to 'heartbreaking' NRL injury

Brett Morris's dazzling NRL career could be over in the most agonising way after he suffered a serious knee injury in the Sydney Roosters' 38-4 win over Newcastle.

On a night in which teenage halfback Sam Walker dominated to continue his meteoric rise, the Roosters were left devastated by the injury to their stand-in skipper for the game.

'TOUGH TO SEE': Fan fury over NRL veteran's post-match move

'DON'T GIVE A SH*T': Ricky Stuart rages in angry post-match spray

Defying his age, the 34-year-old Morris is still considered one of the best wingers in the league after 276 games but he was left in tears after suffering a suspected ACL injury in the dying minutes on Saturday night.

After being bundled over the sideline, the ex-Kangaroos and NSW Origin hero refused help from a medicab, opting to walk off the NRL field as a player for possibly the last time at McDonald Jones Stadium.

"It's one of the proudest and worst shed I've been in," said Roosters coach Trent Robinson.

"I've got a group of guys who love each other and love playing together and we're proud of the way we're playing and then you've got a guy who's a legend of our game, one of the best wingers we've ever seen and he's possibly just finished his career.

"It's just flattening. Extremely flattening. It's hard to explain."

Adding to the Roosters' woes, Queensland prop Lindsay Collins is also believed to have ruptured his ACL, ending his season.

Both will go for scans to confirm what the Roosters believe they already know.

It adds to an already astonishing injury toll for the Roosters that includes Luke Keary, Boyd Cordner and retired co-captain Jake Friend.

There was an outpouring of support for Morris after he went down.

Roosters victory soured by devastating injuries

Until Collins and Morris went down, it was all roses for the Roosters who romped to a 20-0 lead after just 20 minutes.

Newcastle are famous for their former No.7 but teenage halfback Walker put the Knights to the sword, laying on six tries beneath the shadow of the Andrew Johns Stand.

Amazingly, the 18-year-old in just his fifth NRL game was the best player on the field for the second week in a row, showing the consistency of a seasoned campaigner.

His five try-assists and four-pointer of his own take his incredible tally to 11 try assists and three tries from his first five NRL games.

Each week that passes makes it more unbelievable that Walker was simply a back-up halfback for the Roosters, who may not have been unleashed so early had Keary stayed fit.

Daniel Tupou's try in the sixth minute put the winger at outright third on the Roosters' all-time tryscoring list with 105 above Bill Mullins (104) but within reach of Shaun Kenny-Dowall (121) and Anthony Minichiello (139).

And while it was a sorry night for his brother, Josh Morris claimed a hat-trick in the rout while tries to Matt Ikuvalu and Angus Crichton further exposed the defensive ineptitude of the Knights' edges.

In seriously worrying signs for the Knights, last year's finalists have now won just three of their opening eight games.

"Whether it's a confidence thing or whatever, we need to find some solutions and find them quick," said coach Adam O'Brien.

Complicating matters for the Knights, halfback Blake Green suffered a rib injury that will see him sidelined for next weeks' game against Canberra.

Watch 'Mind Games', the new series from Yahoo Sport Australia exploring the often brutal mental toil elite athletes go through in pursuit of greatness:

Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.