The 27-year-old, who joined City from rivals Manchester United two years ago, ignored Mancini's instruction to warm up early in the second half.
The matter will now have to be referred to City's owner, Sheikh Mansour Bin Zayed Al Nahyan of Abu Dhabi, but his largely unprecedented behaviour left Mancini fuming and vowing never to pick him again.
Mancini, looking visibly shocked, told a news conference: "I am really disappointed because it is Carlos.
"This can't happen in a top club - to refuse to go in to help his team-mates. What I said to Carlos is between me, him and the team.
"But if we want to improve as a team Carlos can't play with us. With me, he is finished."
There was some confusion at the time as to why Mancini brought on defensive midfielder Nigel de Jong instead of Tevez after 56 minutes with City trailing 2-0.
Mancini explained that he told the Argentine to get warmed up to come on with around 35 minutes to play, telling him that he believed he could help change their losing 2-0 position.
Mancini said: "He refused to warm up and again refused to go on the pitch. If a player has a lot of money to play for Manchester City... he can't play, never."
TV pictures showed Tevez shrugging and shaking his head when one of City's coaching staff spoke to him on the bench.
UNEASY TRUCE
Tevez has had an uneasy truce with City since angling for a move away from the club over the last year, citing family reasons.
He has only played one full match this season, in last week's win over Birmingham City in the League Cup.
He made a nine-minute appearance as a substitute in City's opening Champions League match two weeks ago against Napoli, and has also made two substitute appearances in the Premier League and started one game.
Tevez has never been far from controversy since moving to England and West Ham United with fellow Argentine Javier Mascherano in 2006, transfers that caused huge problems because their rights were owned by a third party, Media Sports Investments.
The issue, which dragged on for months, eventually saw West Ham being fined 5.5 million pounds by the Premier League and after one season at the Hammers Tevez joined Manchester United in 2007.
Although he was part of the United team that won the 2008 Champions League Final against Chelsea in Moscow, he fell out with the club during the following season and joined United's rivals and neighbours City at the start of the 2009/10 season.
The deal, reported to have cost City around 32 million pounds, was also worth a reported 225,000 pounds in weekly wages to Tevez.
However, he soon let it be known he was unhappy in Manchester because he was missing his daughters in Argentina and came close to leaving the club in the close-season despite May's FA Cup triumph. A proposed move back to Brazil and Corinthians broke down, though.
