Jerome Kaino, Scott Barrett and a handful of fringe backs are among those playing for All Blacks Test spots when they face the Barbarians at Twickenham.

While the club side are vowing to play attacking rugby in Saturday’s tour opener, All Blacks coach Steve Hansen is treating the match like a Test – with “wriggle room”.

It also doubles as a trial of sorts ahead of three tour Tests, against France, Scotland and Wales.

The last-start loss to the Wallabies in Brisbane has made some positions more contestable, most notably at lock.

Barrett has struggled in the last three Tests to fill the enormous boots of Brodie Retallick, with the world class forward having taken an extended break for personal reasons.

Fourteen-Test veteran Barrett admitted he hasn’t enjoyed his best form, a blunt self-assessment which Hansen didn’t dispute.

“It was probably a pretty honest appraisal from Scotty. It’d be good if he steps up,” Hansen said.

“There’s been an opportunity there for a few weeks. It’s just waiting for someone to take it.”

Barrett’s locking partner this week is the more Test-hardened Luke Romano, who impressed in a rare start against Argentina in Buenos Aires and could yet earn promotion to partner Sam Whitelock in Paris next week.

Kaino’s first All Blacks appearance since the British and Irish Lions series gives the 34-year-old a chance to prove he’s not ready for the Test scrap heap.

Liam Squire and Vaea Fifita are mounting cases to take over permanently on the blindside flank but Hansen is reluctant to place pressure on Kaino, whose All Blacks debut featured a try against the Barbarians in 2004.

However, Hansen wants to see signs of the veteran’s trademark muscle.

“He’s a physical player, a good ball-runner,” Hansen said.

“He won’t have had a lot of rugby so the gas tank will be running on empty pretty, I’d suggest.

“I’ve told him, I don’t care if you play 30 minutes. Just give me everything you’ve got and then we can build on that.”

Further out, the likes of midfield backs Anton Lienert-Brown and Ngani Laumape; wingers Waisake Naholo and Seta Tamanivalu; and fullback David Havili aren’t out of Test contention.

Rather than trying to match the Baabaas’ expected fireworks, Hansen wants his backline to play with structure, at least to begin with.

“There’s plenty of wriggle room (to play expansively) but you’ve got to earn the right to do that first,” he said.

“Our guys like to play, it’s in their DNA. But a lot of spilled ball gives a lot of opportunities. We need to look after the rugby ball.”