MANCHESTER //It can be the winger's lot that his position, particularly if he hugs the touchline, can bring him closer to his manager than many of his teammates.
Generally they seemed to involve defensive discipline, a subject of rather greater interest to the Italian than the Englishman.
It always appeared a reason why Mancini was reluctant to trust Johnson.
Now, as the winger returns to Etihad Stadium for the first time since his August move to Sunderland and his native North East, a different message came from his former manager.
"I like Adam," Mancini said. "He is a good player and a good guy."
Johnson spoke similarly fondly.
"I've never been back to an old club in my career, but I had great times there, winning the league and FA Cup," he said. "I'll always see it as a big part of my career. I'm looking forward to going back and seeing a lot of old friends there."
Sunderland's summer signing frustrated Mancini at times with his lifestyle but the Italian was an admirer of his ability.
However, a crowd favourite still became a back-up plan, deprived of action on the major stages.
Consider Johnson's final season in Manchester. While he scored six times and featured in two-thirds of league matches, he started just over a quarter. Only three of those were away - at Blackburn Rovers, Sunderland and Aston Villa. He began home games against Swansea City, Wigan Athletic, Villa, Stoke, Fulham, Blackburn and Bolton Wanderers.
In other words, he never started against a side who finished in the top eight. His unpredictability seemed to count against Johnson, never fully trusted by Mancini despite decent levels of performance.
"I think Adam played well here," said Mancini. "The problem may be that he didn't play always. For young players like him it is important to play every game."
It may constitute a warning to Scott Sinclair, another English winger and the man signed as Johnson's replacement, that he is destined to be a squad player. Unable to dislodge David Silva and Samir Nasri from the side, Johnson's difficulties were compounded his status as the fall guy. He became the first man substituted when Mancini wanted to change tack.
He was hauled off after 39 minutes against Villarreal in the Champions League and at half time versus Manchester United in the FA Cup, both in tactical switches. He ended the season a fringe figure, one ready for a new challenge.
"He wanted to play every game," Mancini said. "Here it was difficult."
Hence the move to Sunderland, the town of his birth. Johnson has not featured frequently there, either, but that has been due to a thigh injury rather than managerial choice.
This should be just his second league appearance since his £10 million (Dh59.5m) move. Mancini expects him to excel. Indeed, he believes his talent may shine too brightly for Sunderland's liking.
There was a scramble for Johnson's services in 2010, when City signed him from Middlesbrough, and their manager said the elite clubs will come calling again.
"He will do well for Sunderland and go to another top team because he deserves this," Mancini said. "I think he is a really good player."
The worry for City is that he proves it today.
Should a slaloming run take him past a series of teammates, should a cross be delivered on to the head of the prolific Steven Fletcher, should a left-footed shot curl into the corner of Joe Hart's goal, there will be a sense of what might have been.
And yet in the broader scheme of things, his was a move that should suit everyone: City, Sunderland and Johnson himself.
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