Discussing new Blues owner Todd Boehly, Souness wrote for the Daily Mail: "In his hurry and enthusiasm to get Chelsea supporters onside, he has just spent the thick end of £300million in the summer transfer market, appearing to do all the business himself. I do hope I'm wrong in that assessment.
"Unless you have a bottomless pit, the money they have spent on Marc Cucurella makes no sense, considering Chelsea already had Marcos Alonso, Ben Chilwell and, at a push, Reece James in the same position.
"Is Cucurella that much of an upgrade on them? I don't think so. Chelsea only seem to have taken him because Manchester City wanted him.
"I get that they needed centre backs because of Antonio Rudiger and Andreas Christensen going and having 37-year-old Thiago Silva, an age when your game can fall off a cliff inside a month. But £70million for Wesley Fofana? At 21, he only brings potential.
"The upside to signing Pierre-Emerick Aubameyang on deadline day is that Chelsea now have a striker who has scored goals in the Premier League, something notoriously hard to find.
"The downside is that he's 33 and has a dodgy gene somewhere. Mikel Arteta did very well for Arsenal, and for his own longevity as manager, by getting Aubameyang out of the building and seems to have found an upgrade in Gabriel Jesus.
"If you want to indulge Aubameyang, then you risk heading down the same road as Arsenal did with that fool Mesut Ozil, who got in his armchair the minute Arsene Wenger put him on a ridiculously inflated salary.
"Boehly certainly seems convinced he knows what he's doing, even though Marina Granovskaia and Petr Cech, who provided the football knowledge for Abramovich, have had enough and are off.
"He is the latest in a long line of wealthy individuals to come into football thinking the game is easy."