Manchester City will look to strike an early psychological blow in the Premier League title race when they host Manchester United on Sunday.
The local rivals have battled for the crown in each of the last two seasons, with City emerging triumphant in 2011-12 before United re-established their supremacy a year later prior to Alex Ferguson's retirement as manager.
David Moyes has since taken the helm at Old Trafford and, aside from a defeat to league leaders Liverpool at the beginning of the month, the former Everton boss has made a solid start.
The teams have posted identical records going into the contest - having both taken seven points from four games - and there is likely to be no shortage of motivation ahead of the clash at the Etihad Stadium.
United emerged 3-2 winners in the same fixture last term, Robin van Persie scoring the winner with a late free-kick, and Pellegrini knows the importance of atoning for that defeat.
"I don't need to be here to know how big this derby is," Pellegrini said. "Playing against Man United at home we must win, it's more important to win than to not lose."
City will be boosted by the return of captain Vincent Kompany, the defender set to make his first Premier League appearance since suffering a groin injury in the season-opening 4-0 win over Newcastle United.
However, creative midfielder David Silva will not be involved after failing to recover from a thigh injury, while defenders Gael Clichy (thigh) and Micah Richards (hamstring) are both doubts.
United, meanwhile, are likely to be without striker Danny Welbeck due to a knee problem, and defenders Phil Jones (ankle) and Rafael (hamstring) could also miss out.
The visitors will, however, be able to call on in-form forward Wayne Rooney, who has either directly scored or provided the assist for 40 goals in his last 44 Premier League outings.
And the former Everton man insists he is enjoying life at Old Trafford again, despite having been strongly linked with a move to Chelsea during the transfer window.
"I feel good and am glad to be out playing," Rooney commented. "It's good to work under him (Moyes) and hopefully we'll be successful together. I feel great."
|16||S. Agüero||16' 47'|
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