Sir Alex Ferguson insists he welcomes the challenge of Manchester City because it prevents his club becoming complacent.

Ferguson believes City may still add to its squad before the transfer window closes - he has previously stated he expects Samir Nasri to move there from Arsenal - and that Manchester United has proved before they can cope with the arrival of the super-rich.

Roberto Mancini's side are United's opponent in the Community Shield on Sunday but Ferguson will not change his approach to the game being just another part of pre-season preparations, and that he would resist getting "emotional" about the clash.

The last time the clubs met at Wembley was in April when City triumphed in the FA Cup semi-final, but Ferguson is looking to a long-termer success over United's local rival.

Ferguson said: "Because of the particular facet of the club that they have the money to spend I thought maybe they would spend more this summer and that may still happen, they may still sign a couple more players.

"We get this almost every year when clubs round about us buy, and that's how you view the importance of winning the league these days.

"Chelsea had this great spell of buying when Jose [Mourinho] first went there and we accepted that challenge. It's good to accept challenges, it keeps the complacency away from your door and we carry on as best as we can."

In terms of the Community Shield, Ferguson is likely to make his team selection based around planning for the start of the Premier League season a week later.

He told a news conference at United's training ground: "I have always viewed the Community Shield as a stepping stone to the first game of the season.

"It's very easy to get emotional about this type of game but I don't think we will be changing our policy.

"There may be two or three players who need the game on Sunday."

Ferguson revealed that Michael Carrick is likely to miss the Community Shield after picking up a slight Achilles problem in Edwin van der Sar's testimonial on Wednesday.

Darren Fletcher, Antonio Valencia and Rafael are all back in training however.

Ferguson confirmed the young Mexican striker Javier Hernandez will miss the start of the league season as a precaution after he suffered from a concussion last month.

He added: "Chicharito won't be involved for maybe another two or three weeks - considering he had a concussion some years ago we are just playing safe with that but he should be back by the end of August."