Retirement is a difficult enough call for many professional sports stars, and when you are a legend - having been feted for many years - it can be trickier than most.
Some depart at the top or at least on their own terms, others carry on too long, and plenty make comebacks both good and bad.
Richie McCaw is into his twilight zone and the All Black legend's future is certainly up for discussion. The most heated debate may end up happening in McCaw's head. And after he does quit, how public will his post-playing career be? We look at 10 sporting greats and how they got to bow out.
WAYNE SHELFORD - the Buck stopped there: Remember where you were on hearing that Buck had been axed? A lot of people do because it was such a huge shock. The year was 1990, and the worshipped All Blacks leader was dropped out of the blue. He tried to make it back for the 1991 World Cup and was last seen in a New Zealand XV. The man deserved better, but he's always seemed to accept life's ups and downs.
What came next? James Dean-like, Shelford's aura grew because he was cut down prematurely. The most famous New Zealand sports axing remains a murky business. Shelford coached North Harbour and a TV documentary caught his blunt communication style on one occasion.
MARTINA NAVRATILOVA - long service:The greatest women's tennis player quit singles in 1994 with a loss, at the grand age of 37.
What came next? The call of the court was too strong and after a little break - during which she made furniture and wrote mysteries - Navratilova returned predominantly in doubles and with success. She picked top partners in a bid to go out a winner at the US Open in 2006, and managed to do so in the mixed event when aged nearly 50. She once said her twilight was longer than most other careers ... and that was before the comeback.
SIR RICHARD HADLEE - perfect lines: The famously organised Hadlee had an almost perfect departure. Already knighted, he retired at the top on his own terms in 1990 with a five-wicket haul against England, including a wicket with his final delivery. The only glitch - New Zealand lost.
What came next? The great man can recall his every move and statistic as if it were yesterday. He was national selection manager for a spell.
JOHN EALES - leaving on a high: Trust Eales. The giant Wallaby lock's final test against the All Blacks in 2001 brought another victory. That gave him the Tri Nations trophy and Bledisloe Cup to go with the World Cup, won for a second time in 1999. Nothing was out of place with Eales, including the ideal retirement. Even his hair appeared unmoved by test action.
What came next? Surprise, surprise - everything appears to be going to plan.
SIR COLIN MEADS - presidential honour: His last series against the amazing 1971 Lions team did not go well - gone were the glory days of the 60s and he was overlooked for the 1972/73 northern tour. Meads was given a two-game farewell in 1973 playing for a Presidents XV against the All Blacks. In those days, the union president was apparently more important than the most famous All Black of them all.
What came next? A bit of everything including more TV advertising time than other All Blacks put together. So we don't have to pine for Piney. Held lots of top rugby posts including All Black selector, but was tainted for a while by coaching the rebel 1986 Cavaliers in South Africa.
MICHAEL JORDAN - teary farewell: His Air-ness had three shots at retiring - including a stint in baseball - finally managing to walk away at the Washington Wizards in 2003 aged 40. He still had the goods but wasn't happy with the blokes he was on court with. Jordan, the team president, even made his star recruit cry, regularly. Anything was going to be a step down from those amazing Chicago Bulls.
What came next? Making money and lots of it including through favourable terms for an increasing stake in an NBA franchise.
MUHAMMAD ALI - I am the greatest ... tragedy: Sick and sad. Ali kept stepping into the ring, to the age of nearly 40, despite showing signs of tremors that became Parkinson's syndrome. Are there any boxers who know when to give up?
What came next? Dreadful physical decline although the famous spirit managed to shine through.
GEORGE BEST - bad liver: The Northern Ireland football freak finished his superstar years at Manchester United at 27 and played around the world when well past his amazing prime. Trying to coax the genius out of the bottle was too tempting for more than a dozen clubs.
What came next? Alcoholism always had Best's number. It killed him at the age of 59 in 2005.
SACHIN TENDULKAR - untouchable: No selector would have been brave enough to blade the almost God-like Indian cricket batsman. Social media were on his case, though, and the media circled the delicate subject, as he struggled with a lean trot. Tendulkar made the call, at 40, late last year and the West Indies were rushed over to ensure a farewell on home soil.
What came next? Too early to tell but put it this way, there are plenty of options.
WALLY LEWIS - king hit: League's most charismatic playmaker lost the club captaincy, was shifted to the forwards then out of the Broncos by master coach Wayne Bennett and his test career was ended by a shock Kiwis victory in 1991. The King went from the absolute heights to the wooden spoon depths in his final days as player-coach with the Gold Coast Seagulls.
What came next? More coaching disappointment, including with Queensland, and epilepsy which he says has obliterated memories of his playing days. Lewis can now be heard stating the obvious as a match commentator.