Signed for £8million from Middlesbrough on deadline day, the 22-year-old left to a standing ovation six minutes from time after providing most of the thrills on a chilly evening.
It was Johnson who won the penalty that Tevez converted to put City ahead. And although fellow new-boy Patrick Vieira set up Adebayor to seal victory, it was Johnson who kept Bolton on the back foot and ensured there was no second away point of the season for Owen Coyle, whose only other one came on this ground in November when he was still at Burnley.
It is a run that must end quickly given Bolton could easily find themselves in the drop zone after tomorrow night's games, and facing Coyle with a massive job to prove it was not a mistake to bring him in to replace Gary Megson.
While Vieira required no introduction on his home debut, Johnson remained a bit of an unknown in these parts.
Not in his native north-east though, where he was rated good enough to merit a place in the Middlesbrough line-up, aged just 20, even though Stewart Downing occupied his favoured left-sided midfield berth.
Those days on the right flank have served the England Under-21 star well by the ease with which he swapped wings to unsettle the Bolton defence.
City were probably glad they made their deadline-day purchase too.
Without Johnson's swift movement and nimble feet, Roberto Mancini's men might have been in trouble against a Bolton side, trying to metamorphosise into a passing team under Coyle while at the same time desperately attempting to stave off relegation.
The arrival of Jack Wilshere should help.
Arsene Wenger clearly approves of Coyle's approach to the beautiful game and Wilshere brings an element of silk to go with the steel Bolton will also need if they are going to survive.
What the Trotters can certainly do without is the kind of rash tackle Paul Robinson made to chop down Johnson, when the only place he seemed to be heading was over the goal-line.
Referee Mike Jones had no doubt it was a penalty despite Robinson's protests, TV replays indicating the Bolton full-back was engaging in a cover-up exercise given the ridiculous nature of his challenge.
Not that Kolo Toure did any better when he scrambled across Johan Elmander, sending the Swede tumbling to the deck as he was about to reach a loose ball with his back to Shay Given's goal.
The protests were just as fierce but this time Jones said no, denying Bolton a chance to level Carlos Tevez's 19th goal of the campaign after Jussi Jaaskelainen had failed to keep the South American's poor effort out.
Bolton could have done with getting Wilshere into more central positions because with a bit more guile they could easily have levelled, such was the impetus they gained at the start of the second period.
As has been pointed out to Wenger repeatedly over the past few days, possession and passes are all very well, but football's hard currency will always remain goals and points.
Mancini was sufficiently disturbed to abandon his solid three-man midfield line by bringing on Shaun Wright-Phillips for Wayne Bridge, a move that involved a significant reshuffle given one is a right-winger, the other a left-back; Gareth Barry's adaptability allowing him to fill the latter role.
The move was unorthodox. But it worked a treat, unlike Bolton's offside trap as the visitors failed to keep tabs on Adebayor as he ran onto Vieira's elegant chipped through ball.
A chest control and crisp, volleyed finish came straight out of the textbook and Adebayor raced away to celebrate.
Bolton continued to huff and puff until the final whistle, by which time Johnson had departed to a standing ovation he is set to receive plenty of on this evidence.