North Queensland winger Antonio Winterstein has announced his retirement from rugby league on Wednesday, effective immediately.
Winterstein played 166 of his 213 NRL games with the Cowboys, and won the 2015 premiership with North Queensland in one of his strongest seasons at the club.
The 30-year-old underwent more scans on his troublesome knee over the past few weeks, and was advised by the club's medical staff to retire from the game in the interest of the long-term health of his knee.
Winterstein fronted the media on Wednesday, and thanked all of those who had made an impact across his NRL journey.
"First of all I would like to sincerely thank the North Queensland community for accepting me with open arms," Winterstein said.
"Since the day my family and I arrived this has felt like home. You have supported me through the good times and the bad and this place will always hold a special place in my heart.
"To all the Cowboys members, fans and partners, I truly believe you are the best supporters in the NRL and thank you for playing such a major part in making the North Queensland Toyota Cowboys the club it is today.
"Finally to my teammates and the staff at the Cowboys, I cannot thank you enough for making my time at the club such a special experience."
Cowboys Director of Football Peter Parr also spoke on Winterstein's announcement, and wished him well in the future.
"In Antonio's first seven years at this club we played finals every year – that's not a coincidence," Parr told reporters.
"He's one of the toughest players I've seen in my time at this club and how long he played with a chronic knee condition highlights that. The way he has dealt with this injury has helped build the culture and professionalism that is part of our club now."