When QPR last visited Eastlands three months ago, the west London club were just minutes away from ruining City’s attempt to become English champions for the first time in 44 years.
City needed a win against Mark Hughes’s relegation-threatened side to guarantee the title, but they trailed 2-1 heading into stoppage-time.
That set the stage for an an incredible finale which saw Edin Dzeko equalise before Sergio Aguero’s winner with virtually the last kick of the season ensured Mancini’s team finished top, above United on goal difference.
Although City have made an unbeaten start to their title defence, Mancini has been underwhelmed by his side’s performances in a 3-2 win over Southampton and a 2-2 draw at Liverpool.
The Italian believes fatigue after Euro 2012 is to blame and he rested Spanish midfielder David Silva for last weekend’s trip to Liverpool.
“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.”
While City strive to rediscover their rhythm, United have also made a spluttering start, losing at Everton before an error-strewn 3-2 win over Fulham that was marred by an injury to Wayne Rooney which will sideline the England striker for up to four weeks.
With Rooney, who this week denied rumours he could quit United after reports of a row with manager Sir Alex Ferguson, recovering from a nasty thigh gash that required stitches in hospital and Bulgarian striker Dimitar Berbatov set to join Fulham, van Persie will be expected to step into the breach.
The early signs are good. Van Persie marked his first United start with his maiden goal for the club against Fulham and the Dutch striker, a £24 million signing from Arsenal, already looks comfortable in his new surroundings.
Ferguson’s defensive options could also be boosted by the return from injury of centre-back Jonny Evans, which would allow Michael Carrick to return to midfield after he was deployed at the heart of United’s defence for the last two matches.
“I’ve had a few setbacks over pre-season where it’s not gone as planned. Now everything’s behind me and I can kick on with the season. Hopefully I’ll be in contention for Sunday,” Evans said.
Arsenal travel to Liverpool on Sunday still looking for their first win and first goal of the season after 0-0 draws with Sunderland and Stoke.
Van Persie’s exit has clearly shaken Arsenal’s belief, and Gunners boss Arsene Wenger, who has seen a host of top players leave in the last year, still faces a battle to persuade England winger Theo Walcott to extend a contract which expires at the end of this season.
“Theo has one year to go and that is simple. We have to find an agreement with him on whether to extend the contract for a longer period or not,” Wenger said.
“That is what we want to do and I think Theo loves the club. Contrary to what some media write he is not obsessed by money, there is just a little difference we hope we can, at some stage, find an agreement with.”
England striker Andy Carroll should make his West Ham debut against Fulham after completing a season-long loan move from Liverpool.
Fixtures (1400GMT unless stated)
Manchester City v QPR (1630GMT), Swansea v Sunderland, Tottenham v Norwich, West Brom v Everton, West Ham v Fulham (1145GMT), Wigan v Stoke
Liverpool v Arsenal (1230GMT), Newcastle v Aston Villa (1500GMT), Southampton v Manchester Utd (1500GMT)