Italian striker not present on the bus parading the team around the city centre, with the former Inter man reportedly en route to his homeland to begin Euro 2012 preparations
The forward played a vital role in City's final-day comeback against QPR on Sunday, providing the assist for Sergio Aguero's title-clinching goal.
However, he is believed to have skipped the post-match celebrations and flown back to his homeland of Italy, casting doubt on his future at the club. The 21-year-old was reported to have landed at Bergamo airport on Monday afternoon having been included in Italy coach Cesare Prandelli's provisional squad for Euro 2012 24 hours earlier.
Balotelli also missed the parade after City's FA Cup triumph last season and failed to turn up to collect his Young Player of the Year award earlier this month.
He has been involved in a number of controversies this season, including calling out the fire department after setting off fireworks at his home prior to the Manchester derby at Old Trafford.
The Italian went on to score in that game, revealing the now infamous 'Why Always Me?' T-shirt and has rarely stayed out of the spotlight for long.
A challenge on Arsenal's Alex Song which went unpunished during a match in April incited Arsene Wenger to call for a lengthy retrospective ban for the forward.
After that match Mancini said the striker would not play again because of the horror tackle but went on to explain that he had believed Balotelli would receive a lengthy ban.