Chelsea boss Andre Villas-Boas expects Manchester City to be serious challengers for the Premier League title this season.
City have already signed Sergio Aguero, Gael Clichy and Stefan Savic, while they are in the market to sign a further midfielder before the transfer window closes. And their recruitment drive has not gone unnoticed by Villas-Boas.
He said: "I think it's pretty clear that they are building a squad to fight for the title. It's for Mancini to say what his objectives are but my personal perspective is that they are making good signings and that they can threaten for the league.
"I think Man United as the title holders will be a reference for everybody but you can see the amount of activity Manchester City have had in the market. It's pretty clear they have a title objective as well.
"Liverpool did more or less the same, Tottenham want to get back into the top four so they'll be challenging and Arsenal are always a threat - we haven't seen the last of them in the transfer market - so everybody is strengthening and as long as everybody feels happy with what they have, everybody competes in a different way."
Though Chelsea have not been nearly as active as City, United or Liverpool so far, they have already signed - and loaned out - goalkeeper Thibaut Courtois, agreed a fee for Barcelona midfielder Oriol Romeu and are apparently still very much in contention for Anderlecht's Romelu Lukaku and Palermo's Javier Pastore.
"The players that we have shown interest in are young and looking to the future of the club," Villas-Boas said. "You might see similar moves in the future from us. It is one of the oldest squads in the Premier League, we respect them and we are happy enough with the quality that we have to challenge for the title, but we are also looking into the future.
"We are so comfortable at the moment with what we are getting because of the young players we have. Things for the future are brighter for us in that respect."