The Blues signed £32m striker Diego Costa, his Atletico Madrid team-mate Filipe Luis and former Arsenal captain Cesc Fabregas from La Liga.
They got most of their business done early and always seemed to be in control
Mourinho secured the return of club legend Didier Drogba before snapping up Loic Remy in an £8.75m deal from Queens Park Rangers after Fernando Torres’s exit.
And former Liverpool centre-half Carragher believes Jose Mourinho is the clear winner in the summer transfer window after strengthen key areas of his squad.
“Chelsea, without a doubt,” Carragher wrote in his Daily Mail column.
“They got most of their business done early and always seemed to be in control. The way Diego Costa has started is so impressive and we’ve still not seen Filipe Luis, who is a top player.
“And the money they’ve spent is not too bad when you compare it to United.”
Former Arsenal defender Martin Keown backed up Carragher’s claim, highlighting the big-money sales of David Luiz and Romelu Lukaku as a shrewd pieces of business.
“It’s a full house. Chelsea won it the day they sold David Luiz for £50m. And then they got £28m for Romelu Lukaku. Unbelievable business. Financial fair play rules have made them become better negotiators.”
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