KEY POINTS:
They share a love of rugby but one is allowed to pursue that affection at all levels around the globe while Nacewa, that gifted versatile attacking back for the Blues, is restricted in his rugby career.
It is a sad old case that a few minutes on the park as a substitute for Fiji against Scotland at the 2003 World Cup, means Nacewa is ineligible to play international rugby for any other nation.
He has ignored every subsequent request to turn out for Fiji again, hoping the code's IRB rulers will grant him an exemption to change allegiance and be available for New Zealand where he plays all his rugby.
Meanwhile, Gatland is the latest in an expanding group of coaches who have added another country to their coaching credentials. That list is top-heavy with New Zealanders like Ross Cooper, Alex Wyllie, John Mitchell, John Kirwan, Graham Henry, Steve Hansen, Peter Thorburn, Robbie Deans and Gatland who has joined Wales after a previous stint with Ireland.
There are others such as Scott Johnson, Eddie Jones, Dave Waterston and Nick Mallett with dual-nationality connections. Their expertise has increased the global resources of the sport, added a great deal more colour and experience to the rugby landscape and been a boon for the code.
Gatland's arrival and initial success has been a fillip for the Six Nations and equally, a regular reminder for New Zealand about a good'un who slipped through the system.
Coaches need a career pathway and Gatland saw too many obstacles for him to bide his time in New Zealand any longer. So too Deans, who leaves after the Super 14 to coach the Wallabies because he was bypassed for the All Blacks.
However, Nacewa is not allowed that flexibility.
The IRB argues that he made his choice four years ago when he pulled on the white jersey of Fiji. How intolerant and small-minded.
While the IRB allows a bunch of experimental laws into the game and former Kiwi league players like Henry Paul and Lesley Vainokolo to play rugby union for England, there is no concession for Nacewa. A stand down of a year or two would stop players altering their international loyalty at every promise of selection or increased pay offers. But allowing them that leeway after time on the sidelines, has to increase the game's appeal.
This is not about Nacewa making the All Blacks. It is about someone's right to choose their employer, to change jobs with the same freedom as those at the IRB and NZRU.
Imagine if recent discarded All Blacks like Jono Gibbes, Craig Newby, Casey Laulala, Jerome Kaino, Corey Flynn, Carlos Spencer, Marty Holah, Sam Tuitupou, Saimone Taumoepeau, Angus Macdonald, Mose Tuiali'i, Ma'a Nonu and Clarke Dermody were available to offer their experience and help raise the standard of the international game.
Visualising that is as likely as the IRB making progress on a global calendar for the sport.
