The Citizens have clawed back an eight-point deficit on neighbours and rivals Manchester United to leave the title in their own hands going into the final programme of fixtures.
Mancini claimed that the title race was as good as over after losing 1-0 to Arsenal last month, but the turnaround in fortunes has been astonishing, City claiming maximum points over their last four games with United claiming just four.
|MANCINI NEVER LOST FAITH
That culminated in a 1-0 victory for Mancini's men in the Manchester derby and, after last week's 2-0 success at Newcastle, City go into the final day top courtesy of goal difference.
Mancini feels the defeat at Arsenal may have taken the pressure off his side and spurred them on even more to win.
The Italian said: "In the moment it was good for us, it took off all our pressure. For two or three games we played completely free.
"We believed we could play a derby three or two points behind. We believed always, also when we were eight points behind."
The Italian believes that success on Sunday would be justified as would be testament to, in Mancini's words, the "best" football this season.
|BLUE MOON RISING
|11/2||Manchester City are 11/2 to beat QPR 3-0 on Sunday with bet365|
He said: "We have played the better football, 100 per cent. Even if we don't win, we played the better football."