The inspirational five-eighth, who will leave the club at the end of the season to join the Wests Tigers for four seasons, came from the field late in the first half clutching at the back of his right leg.

He joined captain James Graham on the sideline, who had been ruled out of the game after failing a head injury assessment stemming from a concussion suffered in the 14th minute.

Yet Canterbury rallied in a courageous second 40 minutes, overturning a six-point deficit to notch a fifth win of the season, leapfrogging Canberra into the top eight in the process.

Coach Des Hasler will likely learn Reynolds' fate by the end of the weekend.

"For Josh to leave the field it would've had to be pretty serious," Hasler said.

"That'll be assessed by the docs though, it'll be somewhere between a grade one and a grade three.

"Both sides were fairly wounded, it was a pretty tough game. Obviously we lost a couple early.

"I was really proud of the way the boys stepped up, none more so than this man beside me [Aiden Tolman] who played 80 minutes. He was inspirational for the boys."

The win caps an emotional week for the club after learning Reynolds had opted to join the Tigers - squeezed out of Belmore in order to make room for Aaron Woods who will go the other way, and potentially Warrior Kieran Foran who has been linked strongly with a move to be reunited with Hasler.

Tolman said losing Reynolds was a massive disappointment for the club.

"James Graham summed it up throughout the week, he's a passionate player, he's an inspirational player," Tolman said.

"He's Canterbury-Bankstown born and bred. It is going to be disappointing him leaving next year, what better way to send him out if we keep performing like that every week.

"Players move on in this competition year to year. He's going to be a big loss for us but that's 2018.

"All we can control now is moving forward in this season. What better way to perform than for him."

Reynolds had started the game strongly, showing all of the competitiveness and determination Tigers fans can look forward to next season.

He spun the ball out left just five minutes in to help set up the first of Adam Elliott's two tries, then made a big play in defence moments later, cutting down a rampaging Josh Papalii 10 metres out from Canterbury's line.

Papalii had his own point to prove here. Kangaroos coach Mal Meninga this week cut him from his team to play New Zealand next Friday in Canberra, after Papalii pleaded guilty to a drink-driving charge.

The Raiders are still deliberating over whether or not to slam Papalii with a club-imposed suspension, and the 24-year-old may yet miss the Newcastle clash in two weeks.

Meninga would've been watching closely to see how well Shannon Boyd fared, Papalii's initial replacement in the Kangaroos side.

But Boyd suffered a lower leg injury in the first half and could well be forced to join Papalii in the stands.

"He's [Boyd] hurt the back of his lower leg, I don't know, I'll have to talk to the doctor - hopefully it doesn't [rule him out of the Test] for Shannon's sake," Raiders coach Ricky Stuart said.

"They played better than us and that first part of the second half they had a lot of footy, we had to defend a lot, but that happens in a lot of footy games.

"You've got to be able to control it. We didn't unfortunately. We were too frantic and panicked a bit, they defended very well and out-toughed us.

"We're losing the tight ones at the moment. It's frustrating.

"We have high expectations on our footy and I think that's why you get really let down and disappointed because you have high expectations and when you don't reach those expectations it's disappointing. But we'll turn it around."

All three of Canterbury's tries came down their left edge - Elliott's double and a determined Josh Morris effort which drew him equal second on the all-time ANZ Stadium try scorers list, alongside Bulldogs legend Hazem El Masri.