THE struggling Blues gave coach Tana Umaga a 12-month contract extension on Wednesday but made it clear he needed to turn around the Super Rugby club's fortunes.
Umaga's team are again rooted to the bottom of the New Zealand conference after losing eight of their 11 matches this season.
Blues chief executive Michael Redman said he believed the All Blacks legend still had a role to play in returning the club to the glory days that brought three titles.
"Changing head coach now would mean we throw out three years of hard-earned experience and starting again, which we believe is the wrong thing to do," he said.
"At the same time, the expected shifts in on-field performance are yet to be achieved and we are examining every aspect of team selection, preparation and support as our fans would expect."
The Blues last won the Super Rugby title in 2003, They have made the play-offs only twice since, most recently in 2011.
They hired Umaga in June 2015 after unsuccessful coaching stints by John Kirwan and Pat Lam.
Umaga is in the final year of his contract and the fact he has been offered only a 12-month extension is an indication the club wants rapid improvement.
Umaga, 44, said he understood the situation and accepted he was "in the results business".
"Believe me, no one at the Blues right now is happy with where we are at, but everyone has bought in to our plan, believes in it and works so hard every day to perform," he said.
"There are significant parts of every game where we are achieving that and just a few basic things that let us down."
The Blues said former All Black Leon MacDonald would join Umaga as an assistant coach in the 2019 season.
MacDonald, the coach of the Tasman Makos in the domestic competition, was Umaga's assistant in 2015 when the pair guided New Zealand's under 20s to a world championship.
"We expect the two of them together will form a formidable coaching team," New Zealand Rugby head of professional rugby Chris Lendrum said.
Wellington-born Umaga played 74 Tests, including 21 as captain, leading the All Blacks in 2005 to a Grand Slam victory and a clean sweep of the British and Irish Lions.
After his international retirement in 2005, he joined French club Toulon, where he earned his management stripes as a player/coach.
He returned to New Zealand in 2010, joining the Counties Manukau Steelers, a team he coached to their first Ranfurly Shield success in 2013.
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