Mancini accused Tevez of refusing to appear as a substitute during City's 2-0 Champions League defeat at Bayern Munich last month, saying he was "finished" at the club.
Tevez, 27, denied Mancini's claims, saying the incident was a misunderstanding and that he had only refused to warm-up because he felt it was unnecessary.
"Gordon Taylor, chief executive, attended the hearing with Carlos Tevez on 21 October and was privy to all the evidence presented to the hearing and Carlos' response," said a statement released by the Professional Footballers Association (PFA).
"The PFA's opinion, based on all the evidence presented, is that Carlos Tevez never refused to play for the club.
"This is accepted by the club in that the charge against Carlos made at the hearing was not one of refusing to play.
"As such the PFA considers that there is no justification for a fine other than up to the prescribed sanction of two weeks' wages agreed by the FA, the Premier League and PFA.
"The PFA has informed the Manchester City Football Club accordingly and Carlos will continue to be supported by the PFA in this regard."
It's believed that Tevez's fine totals around £800,000 after he was found guilty of five breaches of contract.
Source: AFP
Source: AFP