"I got the nod from Steve Hansen, who said 'yep it's all good to go'. [Scott] is getting comfortable there with the amount of minutes he's getting at training, and now it's his chance to get a start. He's played a little bit there at the end of games... he's a great athlete, as the Barretts are."
Barrett, who scored a try and was outstanding for the All Blacks on debut as a replacement lock - the defeat to Ireland in Chicago - has started all four of the Crusaders' past matches alongside skipper Sam Whitelock in the second row, but moves to allow fellow All black Luke Romano to start in the No4 jersey.
Robertson's selection allows for an extremely tall pack against the Force, who have one win from three matches this season.
And the key for him is that he will lose little mobility in having the 1.97m tall Barrett on the side of the scrum. Barrett's pace, ball skills and workrate are such that he has the ability to thrive there, creating further options not just for Robertson but also Hansen.
The Crusaders, unbeaten this season, have rarely had an easy time of it against the men from Perth, despite the apparent gulf in quality on paper. And, after three incredible comebacks in their past three matches, the Crusaders would do well to start with a bang this time at AMI Stadium against a team whose future under Sanzaar's potential new structure remains up in the air.
"There will be a little bit of anxiety," Robertson said of the Force regarding their future. "They seem like a really tight group. Traditionally against the Crusaders they've had a lot of narrow defeats and narrow wins. They've been a couple of blowouts but other than that they've done well against us and we know that."
Wearing the No7 jersey for the Crusaders will be Matt Todd after his recovery from a calf injury. Todd has also re-signed with the Crusaders and New Zealand Rugby for another 12 months.
"He's a hot commodity, especially overseas with his style of play, so we're absolutely stoked," Robertson said.
Crusaders team to play the Force at AMI Stadium tomorrow (Friday), kick-off 7.35pm is: David Havili, Digby Ioane, Tim Bateman, Ryan Crotty, George Bridge, Mitchell Hunt, Mitchell Drummond, Jordan Taufua, Matt Todd, Scott Barrett, Sam Whitelock (c), Luke Romano, Owen Franks, Codie Taylor, Wyatt Crockett. Reserves: Ben Funnell, Tim Perry, Michael Alaalatoa, Mitchell Dunshea, Pete Samu, Bryn Hall, Marty McKenzie, Manasa Mataele.