Julian Savea's steady progression, and noticeable lift on the end-of-year European tour in which he overtook Hosea Gear as the All Blacks' best left wing, will be a boost for Hansen, but Jane will be a big loss.
The 29-year-old, who has played 41 tests, scored seven tries last year, including three against Argentina in the All Blacks' Rugby Championship win in Buenos Aires in September. His reliability on the right wing and uncanny knack of scoring tries make him a huge asset for Hansen.
A serious ankle sprain suffered while playing for the Hurricanes kept Jane out of the three home tests against Ireland last year, with Guildford playing in his place.
In a blog on his Twitter account, Jane acknowledged the extent of his injury. "I've got hard work ahead of me to get back on the field but I WILL BE BACK," he wrote.
Kahui has played no rugby since May last year when he dislocated a shoulder playing against the Reds in Brisbane. He wasn't involved in his team's 36-14 victory over the Highlanders in Taupo on Saturday but remains on track to have a hit-out soon - possibly against the Hurricanes in Mangatainoka on February 16. After several shoulder injuries, the 27-year-old, who is in contact training, is right to be wary.
With Conrad Smith and Ma'a Nonu automatic midfield selections, Hansen would have played the quick and defensively sound Kahui on the left wing last year. Hansen's other option there was Highlanders utility Ben Smith.
The losses of Guildford and Jane mean Rene Ranger, who now has a senior role at the Blues, could come into consideration to make a return to the black jersey. Tim Nanai-Williams at the Chiefs could also fancy his chances of stepping up.
But although Hansen has time on his side, Mark Hammett and Todd Blackadder, the respective coaches of the Hurricanes and Crusaders, do not.
Hammett has Savea at the Hurricanes - his other options are the vastly less experienced Alapati Leiua, Matt Proctor and Richard Buckman.
Blackadder has lost not only Guildford but also his probable replacement Kurt Baker, at least in the short term, after the New Zealand sevens player pulled a hamstring in Wellington at the weekend.
In the meantime, wing Sean Maitland, one of Blackadder's former charges who is now playing for the Glasgow Warriors, made a big impact in his first international when scoring for Scotland in his team's Six Nations defeat by England. The loss of the quick and powerful Maitland could be keenly felt at the Crusaders, if not New Zealand rugby.
Inside track
Rene Ranger (Blues): Played three tests in 2010. Considered a centre by Sir John Kirwan but could still play on wing for Blues this season.
Richard Kahui (Chiefs): An All Black recovering from shoulder surgery, Kahui is a shoo-in to make squad this year if fit.
Lelia Masaga (Chiefs): Has played one test for the All Blacks - against Italy in 2009. Quick, but has fallen down the Chiefs' pecking order.
Asaeli Tikoirotuma (Chiefs): Fiji-born Tikoirotuma would be one of the fastest in this line-up. Made his Super Rugby debut last year, so short of experience.
Tim Nanai-Williams (Chiefs): Has pace and X-factor. At about 90kg is a little on the small side.
Hosea Gear (Highlanders): Last year was his big chance but ceded ground to Julian Savea.
Ben Smith (Highlanders): Consistent and able to comfortably cover fullback. Solid if a little unspectacular.
Julian Savea (Hurricanes): All Blacks' best wing in the absence of Jane. Was brilliant at times in his debut All Blacks year.
Andre Taylor (Hurricanes): More of a fullback now. Pushed close for inclusion in All Blacks squad last year.
