Manchester United manager Sir Alex Ferguson believes it would be "foolish'' to rule out a title challenge from Manchester City this season.
City are likely to take their summer spending above £100m before the transfer window closes at the end of the month, and Sir Alex believes that kind of spending cannot be ignored.
Sir Alex believes there are parallels with the big spending of Roman Abramovich when he first arrived in the Premier League, which led to back-to-back titles for the west London outfit.
But he was quick to point out that he does not fear his rivals from across the city at all.
"It would be foolish to ignore developments at Eastlands,'' said Ferguson. "Manchester City do pose a new threat. We have only to look at how well Chelsea did with back-to-back championships after a massive injection of Russian cash to know money can talk.
"All the leading clubs are looking with interest to see how Mark Hughes handles the situation and whether he can make it work.
"We are all looking over our shoulders, though as far as Manchester United are concerned, it is not in fear.''
Ferguson was also quick to praise striker Wayne Rooney after he netted the only goal of the game against Birmingham City on Sunday.
"If you have two or three strikers who can get you 20 it stands you in good stead.'' said Ferguson. "Wayne Rooney is well capable of that.
"I know some of our supporters are still worried that I have not bought a megastar to replace Cristiano. They are concerned because they can't quite work out how we are going to compensate for all the goals Cristiano used to get for us.
"But I am more than happy with our squad and although we have lost a major player, I believe we are on the threshold of a very exciting era for Manchester United.''
There was no argument from Alex McLeish, whose team turned in a creditable performance, without ever quite getting to grips with Rooney's threat. He was also full of praise for Rooney.
"We have seen so many natural footballers over the years, people like Zinedine Zidane and Luis Figo, they are difficult to coach. You can do one or two things in terms of the shape of the team but when he drops into those little pockets, he is hard to pin down.''