"I came home 100 per cent that he was coming to us so that's been difficult for us because we made some decisions over the next three weeks," Kirwan said yesterday.
That assurance went west and deep south yesterday as Nonu chose to cancel his contract, as he was permitted, with the intention of signing a new deal with the Highlanders.
Initially, Kirwan was angry and aghast. Nonu had reneged on his handshake deal and ruptured plans for his backline where the domino effects on his selections would be widespread.
But when he faced a media throng yesterday he was more measured and already looking at life without the All Black second five-eighths.
"I am disappointed. I think that the lateness in the decision has put us in a difficult situation," Kirwan said.
Nonu had changed his mind and indicated that some unspecified history had made him unhappy with the Blues.
"We have to cop it and move on," said Kirwan.
One of his sons did as he told his father; "I'm on Trade Me, do you want me to look for a new centre?"
Nonu was signed to a two-year deal with the Blues but had been able to rip up that contract, a move Kirwan could not explain.
"I think you have to talk to the NZRU about how the contracting system works because if he terminates with the NZRU it makes everything else null and void. Not my department boys," Kirwan added.
"That's how it is, at the end of the day. It is about an individual choice.
"It's a business, it's not personal. I am personally disappointed and that's between Ma'a and I.
"I won't let one person expose this franchise ever. I care and love this franchise in this great city and region of ours, you know that. I am passionate about it.
"We are going to have a fantastic young football team and bring it on."
At that stage a mobile phone rang, prompting Kirwan to ask if it was Ma'a.
Kirwan said he still had to make some calls about his final squad selection with Nonu and before him Mils Muliaina unwilling or unable to be included.
Super rugby was a hard, long tournament and the Blues needed experienced players to help them through that slog.
Many in the squad would be young and inexperienced so they had to get a seasoned group around those with minimal Super Rugby contact. One of those was Nonu's buddy Piri Weepu but the coach was sure he would turn up sharp and ready to play next season.
The Blues meet the Highlanders in round 8 of next year's Super Rugby series and then in round 16 and Kirwan said he would shake Nonu's hand when they next met.
"It's not personal, this is a business, but for me I like to have a lot of love in that business. I want to have people I care about and who want to play for the franchise."
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