Te Maire Martin today announced his retirement effective immediately from the NRL after suffering a bleed on the brain in April last year.
The 24 year-old had been recovering well though he was unable to make significant enough improvement to resume full contact training.
The departing playmaker told the club website: "The last nine months have been extremely difficult... I'd like to thank the Cowboys for their unwavering support."
Martin thanked the club's medical staff before going on to speak about what affect this has had on his life.
"I'm doing well and i have recovered to the point where my day-to-day life isn't affected, I can't get past the contact stage of training which means I can't play footy anymore."
Cowboys Director of Football Peter Parr was full of praise for the New Zealand international saying he had a profound impact both on and off the field.
"He's been a wonderful contributor since he's been here... he has a significant impact on everyone at the club," Parr said.
Martin played 62 games for the North Queensland Cowboys and Penrith Panthers while representing his country on 4 occasions.