Sam Warburton has retired from professional rugby at the age of 29.
The former Wales and British and Irish Lions captain hasn't played since the third Lions Test against New Zealand in June 2017 and had been recovering from neck and knee surgeries following the tour.
Warburton returned to pre-season training with Cardiff Blues this summer but has decided that he will not be able to return to the level that made him one of modern rugby's greatest players.
"Unfortunately, after a long period of rest and rehabilitation the decision to retire from rugby has been made with my health and wellbeing as a priority as my body is unable to give me back what I had hope for on my return to training," Warburton said in a statement.
"To look back on my career, I'm extremely proud of what I managed to achieve."
In 2017 Warburton became only the second player to captain the Lions on two tours. Having already led the Lions to a first Test series victory in 16 years when they beat Australia in 2013, Warburton then captained the team as they earned a historic series draw against New Zealand.
Born in Cardiff in 1988, Warburton made his international debut in 2009 and was named Wales captain at the age of 22 ahead of the 2011 Rugby World Cup, where Wales would make the semifinals.
Warburton then led Wales to a Six Nations Grand Slam in 2012. Injuries limited his appearances the following year as Wales retained their Six Nations crown.
Warburton was then appointed Lions captain by his Wales coach Warren Gatland, who was also taking charge of the tour to Australia. At the age of 24, Warburton became the youngest Lions captain in the team's history.
In 2015, Warburton led Wales at a Rugby World Cup for the second time as his country made the quarterfinals.
Gatland then appointed Warburton as his Lions captain for the second time ahead of the tour to New Zealand in 2017. The series was drawn in dramatic fashion after a 15-15 draw in the third Test at Eden Park, in what transpired to be Warburton's final professional appearance.
"Sam has left the jersey in a better place," said Martyn Phillips, Chief Executive of the Welsh Rugby Union.
"The way that Sam has conducted himself as Wales and Lions captain, on and off the pitch, has been exemplary.
"Even the manner in which he has made this extraordinarily tough decision demonstrates the quality of leader he has become. Sam has had a remarkable influence on the pitch for Wales and I suspect will have a remarkable influence off the pitch for many years to come."
Domestically, Warburton spent his entire professional career with Cardiff Blues, making his debut for his hometown region in April 2009.
His achievements with his club side include winning the European Champions Cup in 2010, becoming the first Welsh side to win a European title.
"We are obviously disappointed to lose a player of Sam's calibre but we entirely understand and respect his decision," said Richard Holland, Chief Executive Officer of the Cardiff Blues.
"Sam was desperate to get back onto the pitch and to give back to Cardiff Blues but he has contributed an immense amount to the entire organisation during the 10 years he has been here.
"He has remained a one-club man, which is testament to his character both as a player and a man. He is a true great of the game and we wish him all the very best for life after rugby."