Newcastle Knights legend Danny Buderus has thanked fans for their support and well wishes.
Buderus was knocked unconscious in the first half of the Knights preliminary final loss to the Sydney Roosters on Saturday night.
He was taken to hospital for scans and was kept in overnight as a precaution, before being discharged on Sunday.
The club says there is some concern for Buderus' lower back after two back operations earlier this year.
He will visit a specialist in Newcastle this week for further assessment.
The weekend's game was Buderus' last with the veteran hanging up the boots after 16 years in the top grade.
The Taree junior made his first grade debut for the Knights in 1997 and is now the club's most capped player having played 257 first grade games.
Buderus says he is thankful for the long career he has had.
"No one wants to finish their career this way but I have been fortunate to play the game I love for this long and for us to finish in the top four this season," he said.
"Thank you to everyone for their well wishes and support, not just last night but throughout my career.
"I love this club and have said on a number of occasions I am forever indebted to it."
Coach Wayne Bennett says Buderus is in good spirits despite his severe concussion.
"He's all good, a few head aches, still a little drowsy but otherwise he's fine," he said.
"I'm trying to convince him his last game was Melbourne."
Bennett says it was a disappointing way for Buderus to finish his career.
"Danny's one of those very unique and special people that you meet not enough in your life," he said.
"I think a lot of the boys felt extremely sad on Saturday night, not so much because of the loss but because of what happened to Danny.
"And I think they felt pretty sad on the ground because it was a long period before he went of the ground.
"He's so highly regard by them all and to see him finish that way was upsetting for a lot of blokes."