During his 180-game career at the Warriors he was seen as an individual talent that might not blossom under the burden of captaincy.
Johnson also had plenty on his plate; as the face of the team, chief playmaker, halfback and goal kicker, and wasn't part of the leadership group at the club in the 2018 season.
But Maguire has always backed Johnson, and the 29-year-old admits he has made progress in that area.
"As a person and a player I've grown," said Johnson. "As you get a bit older you view what works and having Madge's influence, having all those lessons over the years at the Warriors, then coming to the Sharks and growing even more…it's been really helpful. I feel comfortable within this role and feel like I don't need to force it. I'll just be myself and get around the boys as much as I can. "
Johnson is also a Nines veteran.
He featured in the first three NRL Nines tournaments in Auckland (2014-2016), before missing the last event in 2017 due to injury.
And he was electric, especially with his performances in the inaugural year, as the Warriors reached the semi finals, holding a capacity crowd spellbound, with his dancing, weaving feet. He was also brilliant in the 2016 edition, as captain, as the Warriors made the final.
"Obviously you draw on experiences like the ones that I had back in Auckland," said Johnson. "As you get a bit older maybe you can't do the things you once could on the field but certainly your knowledge of the game and and what's important to drive [standards] has certainly grown.
"We have a young, exciting side so it gives [me] a good challenge, and everyone who comes in has a chance to step up and really try and take our jersey and put it in a better place. We get the first chance of doing that this weekend."
The shortened format, with much more space, is tailor made for Johnson's flair but there will be science and structure amid the sizzle.
Maguire took out the Nines tournament in 2015 with South Sydney, a few months after the Rabbitohs had won the NRL premiership. He's put an emphasis on a territorial game, especially critical against Australia on Friday.
"Everybody loves throwing the footy around and that style but whether that wins you comps, we are yet to see," said Johnson. "Madge (Maguire) has won a comp with Souths a few years back and he has made me, and the rest of the group, view the Nines in a different way."
"Having that experience that Madge has been through and relaying that back through our game model and how we actually want to play for the Kiwis, it's very similar, so it will put us in good stead over the next few weeks as well."