The 21-year-old fractured a vertabra in his lower back in the recent game against Leigh, and played on in the second half through the pain.
Lawler will now focus on recovering and getting himself fit for the 2016 season,
We’re disappointed to be without George for the next few weeks,” said Peacock, according to the Robins’ official website.
“But he needs to be commended for his courage and bravery in playing through such an injury. He really is as tough as they come.
“It was only after the game that scans picked up the fracture and unfortunately it means he won’t play again this season.
“However, the specialists and our own medical staff are very confident there will be no lasting damage and we’ll have him back for the start of pre-season training.
“This has been a breakthrough year for George and he’s had an outstanding season playing in a couple of positions.
“He’s earned a new long-term contract with the club and we’re looking forward to him continuing his development in 2017 and beyond.”