Tevez running out of time for FA Cup Final
The 27-year-old Argentine striker has not played since City's defeat at Liverpool on April 11 when he tore a hamstring and missed City's semi-final win over Manchester United.
Mancini told reporters at his weekly news conference that Tevez remained a doubt for Saturday's Premier League game against Everton at Goodison Park and that time was running out for him to be fit for the Wembley date.
"It's very difficult for him to play against Everton, and if he doesn't play against Tottenham, it will be impossible for Carlos to play in the final," Mancini said.
Fourth-placed City lead Spurs by seven points with four matches left in the race for a Champions league qualifying spot.
While doubts remain about Tevez, defender Micah Richards appears to be near to a comeback following his hamstring injury and could be on the bench against Everton.
"Micah is very close," said Mancini.
City are appearing in their first FA Cup final exactly 30 years to the day since they lost 3-2 to Spurs in a replay at Wembley. Stoke are in the final for the first time.