Sunday's Wembley clash gives a spicier-than-normal edge to United's final pre-season encounter.
It also provides the opportunity to avenge last season's FA Cup semi-final defeat by Roberto Mancini's men, which open up the path towards an end to the Blues' 35-year trophy drought.
Not surprisingly, with the Premier League title to defend, Rooney is anxious not to give City any hope of an improvement on their own impressive third placed finish last term.
"You couldn't get better motivation to start the season with a bang," the England striker told Four Four Two magazine.
"I hadn't even thought about it until I turned on the TV and someone was talking about potentially the best Community Shield ever.
"Playing City is the best way to start."
Although the FA Cup semi-final was a disappointing day for United, the Red Devils will never forget Rooney's sensational winner in the Old Trafford league meeting between the two sides a couple of months earlier.
It went a long way towards United's record 19th league championship, although Rooney acknowledges it will be even harder to retain the crown considering the number of challengers jostling for position.
"The names are obvious," he said.
"When you are at a club like Manchester United, you pretty much know what the goals are. We want to win the league, the Champions League and both cups.
"It is pretty simple. Obviously, you fall short sometimes but at Manchester United, you have to keep striving for it."