Former Crusaders coach Leon MacDonald has warned the All Blacks against being too reliant on Beauden Barrett.
Speaking to Radio Sport's Jason Pine, the 56-test former All Black said Richie Mo'unga should be starting "quite a few" of the All Blacks' tests this year, based on his red-hot form for the Crusaders this season.
"I don't think anybody will disagree that Beauden Barrett is world class and one of the best 10s in the world," MacDonald said.
"But the form that Richie's in this year for Super Rugby, he's deserved an opportunity at some point just to show whether he's ready to take that step up and drive the All Blacks in a big test."
All Blacks coach Steve Hansen was quick to play down the Barrett-Mo'unga debate that has emerged over the last few weeks, saying earlier this month that the Crusaders No 10 benefited from "playing behind the Rolls Royce pack".
But relying too much on a player, especially a year before the World Cup could be dangerous, says MacDonald. He believes Mo'unga is "absolutely ready" to take on the All Blacks no 10 jersey.
"If you rely too heavily on any player, but particularly a 10, if you put all your eggs in Beaudy's basket, you'll get unstuck.
"They'll be pretty keen both of them have plenty of game time."
There was no room for Mo'unga in Hansen's 23-man squad for the first Bledisloe Cup test against Australia in Sydney on Saturday.
With Barrett – a two-time World Rugby player of the year – getting the nod at first-five, the rationale seems to be that there is no room for Mo'unga, widely regarded as a specialist No 10, in the All Blacks 23 if he is not starting.
But MacDonald disagrees, saying Mo'unga is more than capable at playing multiple positions.
"I think he could [start on the bench] because Beaudy can play fullback. And Richie plays fullback too, don't forget that, and he plays it really well.
"And the way a lot of teams [are] defending now, you play multiple positions. So quite often you'll find Richie at the back of the field on defence because he's a good counter-attacker and good under the high balls."
Ultimately, MacDonald believes there is room for Mo'unga in the All Blacks squad.
"You can make things happen, whatever way you want. You can cut it up and still get the best out of all your players. There's no reason why Richie couldn't be playing 12 as well at a push if they had a couple injuries in the test.
"He's versatile enough, he's got the skill and he's a good communicator. I think definitely he could make the bench [if he's not starting]."
MacDonald left the Crusaders in 2017 to move back to Blenheim with his family, and is due to join the Blues as an assistant coach next season.