so far, with an unconvincing 3-2 win over Southampton followed by a hard-fought 2-2 draw at Liverpool.
The Italian believes the main reason for City's lethargy is the mental and physical strain on his players after the European Championship in Poland and Ukraine.
Mancini decided to drop one of the key figures in his team, Spain's David Silva, for the trip to Liverpool because he felt the playmaker needed a rest and he does not expect an immediate improvement in Saturday's clash with QPR at Eastlands.
"We don't have all the players in good form," Mancini said.
"The international players started pre-season on July 25. They are not in good form. This is one of the reasons.
"David started his pre-season late and for one week went to Puerto Rico with Spain. He needs training and maybe to play, but not for 90 minutes."
QPR's visit will prompt glorious memories for City after their incredible 3-2 win over the west London club that clinched the title on the final day of last season.
Trailing 2-1 heading into stoppage time, it appeared City had squandered a golden opportunity to win the title for the first time in 44 years.
But Edin Dzeko sparked a dramatic fightback with the equaliser before Sergio Aguero bagged the winner with virtually the last kick of the season to wrestle the title away from Manchester United.
Just three months on, though, Mancini is more concerned with improving his squad than revelling in past glories.
Mancini has been desperate for new faces since the end of last season, when he called for the club's hierarchy to make quick additions to establish City as a European force.
Going into the final week of the transfer window the only purchase he had managed was Jack Rodwell from Everton.
But with the club closing in on the signings of Fiorentina's Matija Nastasic, Swansea City's Scott Sinclair and former England goalkeeper Richard Wright, Mancini could finally get the new recruits he desires.
Mancini will have a similar squad to the side that drew at Anfield last time out, with Aguero, Micah Richards and Gareth Barry all still injured.
However, the QPR team that arrives at Eastlands will look very different from the one that clung onto their Premier League place despite losing to City last season.
Rangers' celebrations that day may have been nothing more than a footnote to the main event but with a place in the top-flight guaranteed, club owner Tony Fernandes subsequently bankrolled several expensive signings for coach Mark Hughes.
With the change in personnel comes a change in expectations, and it is clear another narrow escape will not be satisfactory.
And with one point in the opening two league games of the season, and the 5-0 home defeat by Swansea on the opening day still raw in the memory, former City boss Hughes could do with upsetting the odds at City.
QPR's chances have not been helped by the absence of Mali midfielder Samba Diakite, who has returned home to France because of personal reasons.
"Samba is unfortunately having difficulties with some personal issues at the moment and we are supporting him in every way we can," Hughes said.
"We hope he can overcome this very quickly and get back to being the outstanding player that he undoubtedly is. In the meantime, we are giving him the time and help that he needs."