Lucas, who was NSW's 20th man for the series opener, has become one of the NRL's most effective second-rowers since debuting with the Knights in 2023.
He has been in stellar form since returning from a throat injury in round nine, most recently scoring two tries in the round-13 defeat of Parramatta.
Lucas's attacking power on the left edge appears crucial to the resurgent Knights' hopes of a finals berth this season, given that is the side of the field favoured by attacking weapon Kalyn Ponga.
His new deal means only captain Ponga and marquee half Dylan Brown hold longer deals than Lucas among the Knights' current playing roster.
Lucas had already been contracted for the 2027 season, but his new deal keeps him out of the clutches of forthcoming expansion sides Perth and PNG.
The 25-year-old has impressed first-year coach Justin Holbrook, who has hoisted the reigning wooden spooners into fourth spot on the ladder through 13 rounds.
"Dylan's work ethic is outstanding," Holbrook said.
"The positive attitude and intensity Dylan trains and plays with every day is infectious on his teammates and everyone around him.
"He has become a genuine leader. He backs himself with a respectful self-confidence that has a huge impact and influence on the standards of this group."
The Knights could finish the weekend as high as third on the ladder with a defeat of Melbourne on Friday night.
11°C