MacDonald is an organised and straightforward individual who instantly gains the respect of his players – another reason why the Blues wanted him so badly alongside Umaga. And so while Robertson will have been sad to see his mate go he could have consoled himself with the knowledge that MacDonald wasn't taking his intellectual property to a Super Rugby rival.
That's the second point – the fact that MacDonald will be taking the knowledge gained from a year at the Crusaders, during which they won their first title in nine years, to another New Zealand team, and there are echoes here of Tabai Matson's flirtation with the Blues while he was still under contract as an assistant coach at the Crusaders in 2015.
John Kirwan, the then Blues coach, had made a big play for Matson to move to Auckland to coach alongside him, but his grand plan fell apart after it was revealed in the Herald and Matson remained in Christchurch. After a stint at Bath with Todd Blackadder, Matson is now an assistant coach at the Chiefs.
That in itself is a reminder that rugby is a professional game and coaches can and will move to rival teams, but old habits die hard.
The other aspect is New Zealand Rugby's involvement. MacDonald has joined Umaga on a national contract – NZ Rugby pays for two fulltime coaches at each franchise – and the Crusaders might harbour resentment that in seeking to strengthen the Blues, which the national organisation sees as a crucial franchise in terms of the game here and one that badly needs assistance, they have in turn weakened the Crusaders.
MacDonald must have been awarded a very lucrative contract to move himself and his family to Auckland, and the majority of that, if not all of it, will come out of NZ Rugby's coffers.
MacDonald probably sees a faster pathway to a Super Rugby head coaching role at the Blues than the Crusaders, where Robertson has another year on his contract after this one and will probably re-sign. He can't be criticised for doing what's best for himself and his family.
There will be resentment in the south, but it will lessen as every party gets used to the idea.
Robertson chose his words carefully in a media scrum yesterday when he said: "When he was here I tried everything I possibly could to keep him here but he made the decision for his family to head to Blenheim as he's told us, and now he's a Blue."
Later, Robertson told Radio Sport: "He obviously thinks he can make a difference up there – he's a bloody good coach and a good man so all the best to him. The coaching world is a professional world and people make these decisions.
"It's not a personal thing at all."
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