Blink and you miss a fair bit these days as could soon be evidenced if Daniel Carter's troublesome calf doesn't come right.
This time last year it was Colin Slade who was asked to replace the great man at the World Cup. Then Aaron Cruden had to step in when Slade was injured before Stephen Donald was recalled from his fishing trip to win the World Cup for the All Blacks.
By the middle of this year we were back to Cruden as the obvious successor to Carter, but maybe, just maybe, it is Beauden Barrett who is going to be the man trusted with either starting in the No 10 shirt against Argentina or warming the bench should Carter come right.
All Black coach Steve Hansen has shown himself to have a good feel for when players are struggling. He doesn't make hasty or rash decisions so would not call up Barrett on a whim.
But there are a couple of reasons why the selectors may be leaning towards the younger man rather than Cruden. The first is performance.