On a night Tigers prop Alex Twal was sinbinned for slapping Jaeman Salmon, the Bulldogs moved up to 10th and remain within touching distance of the top eight following Saturday's win at Accor Stadium.
Twal is likely to face suspension in another blow for Benji Marshall's side, who have no hope of making the finals.
And it's hard to pinpoint any moment in time other than Luai's decision to join the PNG Chiefs in 2028 as the catalyst for the Tigers' mid-year implosion.
The Tigers boasted a 5-2 record after the opening eight rounds but have won just two of their 11 games since Luai signed with the Chiefs.
Luai was granted an early release this week to join Parramatta in 2027 and was met with a smattering of boos.
Marshall defended the contribution of his No.6, who had just seven first-half touches as the Dogs - minus Stephen Crichton - raced out to an 18-0 halftime lead.
"He (Luai) went out trying to do his job and obviously the scoreboard got the better of us," Marshall said.
"We were trying to catch our tail there at the back end but he was trying hard."
Marshall said Twal's actions - he returned with less than a minute left and got into another skirmish - were symbolic of the Tigers' frustrations.
"It's probably a reflection of a lot of us at the moment how we're feeling," Marshall said.
Stepping in for Crichton in the halves, journeyman Sean O'Sullivan nudged a 40/20 in the first minute and on the ensuing set Jethro Rinakama crossed over.
Then Lachlan Galvin, who secured his first win against the Tigers since last year's acrimonious exit, dabbed a grubberkick to the in-goal for Josh Curran.
Rinakama had a second chalked off before Enari Tuala squeezed over in the corner.
Luai had little influence and despite starting the second half with a bit more spark, the Tigers were quickly put back on the back foot by another O'Sullivan 40/20.
Heamasi Makasini went closest for the Tigers in the second half but they failed to get over the line through 80 minutes and have scored just 44 points over their five-game losing streak
Latu Fainu was sinbinned for a dangerous tackle in the 65th minute and from there the Dogs cruised home, Matt Burton kicking a penalty goal and scoring a try after the Tigers utility was sent for 10.
Twal's 69th minute slap on Salmon meant the Tigers spent a short period down to 11 men and Curran wrapped up victory with his second try after backing up a Gordon Chan Kum Tong break.
Twal returned for 30 seconds and reignited his feud with Salmon but was spared further sanction as Canterbury claimed their fifth win in seven games.
"I'm really happy with some of the things we've been doing," said Bulldogs coach Cameron Ciraldo.
"Sean's done well tonight, and that's a really good signs for us because we're going to need everyone in the next eight weeks."
6°C