The inevitable has finally come to pass and Blues backline star Isa Nacewa has at last succumbed to the temptations on offer up north, agreeing to join Leinster in Ireland from next season.

The Blues announced today their 25-year-old back utility, capable of slotting in anywhere from first five to fullback, has signed with Leinster and will join them later in the year once his obligations in New Zealand conclude.

The move has been on the cards for some time given Nacewa's growing reputation as a world-class back, his almost unprecedented utility value and the fact that, courtesy of a few minutes as a World Cup replacement for Fiji in 2003, he is not eligible to play for the All Blacks.

The New Zealand-born Nacewa, who qualified for Fiji through his heritage, had for some time hoped to have the IRB's eligibility ruling overturned. But so far any requests have been met with a stubborn refusal at the top level.

Nacewa, who will play a key role in the Blues' quest to save their Super 14 season, said the decision had been a difficult one.

"I really enjoy playing for the Blues and Auckland but am very aware I have to make the most of my playing career while I can," he said. "All of us in this game know it is for a finite time-period so it really comes down to making smart decisions short and long-term.

"Having a shot at the All Blacks was and will continue to be my long-term goal. But the reality is that's not an option for me right now so I have to get on with my career."

The then 21-year-old Nacewa was called into the Fiji squad at the World Cup in Australia back in 2003, playing just two minutes as a late replacement in one match. He has said subsequently he had no idea at the time it would render him ineligible to ever play for New Zealand.

The decision by Nacewa to head north certainly comes as no surprise for either the Blues or Auckland provincial organisations.

"Isa has been in demand for quite some time. He is such an outstanding player to have in your lineup, his authority and leadership is exemplary and Leinster is very fortunate to have him," said Blues coach David Nucifora.

Blues and Auckland CEO Andy Dalton paid tribute to Nacewa's loyalty.

"We have been aware of Isa's popularity overseas and duly impressed at his ability to resist tempting offers in order to continue playing for us and pursue the right to wear a black jersey.

"It is a shame Isa is even in this predicament and I hope long-term there will be a way he can play for the country he was born and raised in. Either way, our doors will always be open to him."

Nacewa made his provincial debut as a 20-year-old and first appeared for the Blues in 2005 against the Highlanders. He has 54 caps for Auckland and 40 for the Blues.

Nacewa's Blues meet the six-time champion Crusaders in Christchurch on Friday night in a match they probably have to win to keep their playoff hopes alive.