Thomson, 30, who has played 28 tests after making his debut in 2008, has been on the outer at the All Blacks recently, having seen Sam Cane, Liam Messam and Victor Vito move ahead of him on the loose forward pecking order.
His selection in Hansen's 32-player squad yesterday to play tests against Scotland, Italy, Wales and England, then, is more about rewarding his previous loyalty than anything else.
"He was the best person on merit for his position so he was selected, no different from numerous other players named who could be possibly leaving," Hansen said. "And in fact there's probably more certainty about them leaving because we don't know what he's doing and he doesn't at this point either. Our job is to pick the best people we can."
Hansen added in a more revealing response about Thomson's plans: "He's played a lot of rugby over the years and played a long time for the Highlanders probably as their go-to man and maybe his body is telling him it's time to maybe go somewhere else. We'll support him in whatever he does. In the meantime he's in good form, I've seen him playing well for Otago and he'll get his opportunity on the end-of-year tour."
Hansen has proven to be a coach who is extremely keen to reward loyalty - his selections yesterday of out-of-form pair Ali Williams and Piri Weepu also show that.
However, given Thomson is leaving New Zealand rugby, questions will be asked about whether it would be more appropriate to reward the loyalty of players who are staying.
Hansen mentioned others gunning for the sixth loose forward position who will be miffed at missing out - they are Canterbury pair Matt Todd and George Whitelock, Bay of Plenty's Tanerau Latimer, who was yesterday named as the New Zealand Maori captain, and Auckland's Daniel Braid.
"It's becoming a very contested position," Hansen said.
"We've got a young guy by the name of [Ardie] Savea playing very well [for Wellington]" and others were playing well.
The only uncapped players named yesterday were Hurricanes and Wellington hooker Dane Coles and Chiefs and Waikato halfback Tawera Kerr-Barlow.
Backs
Halfbacks: Tawera Kerr-Barlow, Aaron Smith, Piri Weepu
First fives: Beauden Barrett, Daniel Carter, Aaron Cruden
Midfielders: Tamati Ellison, Ma'a Nonu, Conrad Smith
Outside backs: Israel Dagg, Hosea Gear, Cory Jane, Ben Smith, Julian Savea
Forwards
Hookers: Dane Coles, Andrew Hore, Keven Mealamu
Props: Wyatt Crockett, Charlie Faumuina, Ben Franks, Owen Franks, Tony Woodcock
Locks: Brodie Retallick, Luke Romano, Sam Whitelock, Ali Williams
Loose forwards: Sam Cane, Richie McCaw (c), Liam Messam, Kieran Read, Adam Thomson, Victor Vito
