Former Chelsea midfielder and assistant manager Ray Wilkins has voiced his frustration at the club's transfer business over the summer.
Over £180m was spent on bringing in Alvaro Morata, Tiemoue Bakayoko, Antonio Rudiger, Davide Zappacosta, Danny Drinkwater and Willy Caballero.
Drinkwater and Zappacosta were Deadline Day signings and the Blues missed out on Ross Barkley and Fernando Llorente, who joined Spurs instead.
Antonio Conte has a number of new faces in his first team but watched the board defy logic to sell the likes of Nemanja Matic, Nathan Ake and Nathaniel Chalobah.
Ake joined Bournemouth in a £20m deal, Chalobah re-joined Watford for £5.5m and Matic linked up with Jose Mourinho at Manchester United, moving for £40m.
Meanwhile, Conte fell out with star striker Diego Costa and the Spaniard seems highly unlikely to play for Chelsea again - despite failing to secure a return to Atletico Madrid.
Matic, 29, had been a regular feature of the Chelsea first team since re-joining the Blues from Benfica in January 2014.
He has started the season in excellent form for his new club Manchester United - Chelsea legend Ray Wilkins is utterly astonished by his sale.
"It’s the worst decision I’ve ever seen," Wilkins told Sky Sports on Tuesday.
"You’ve got a guy here who was paramount to Chelsea along with Kante in the middle of of the pitch, winning the title with Chelsea the year before and all of a sudden you’ve sold him to one of – or the biggest – rivals we have.
"I say we because I am a Chelsea supporter so I’m speaking from the heart when I speak. I just could not see that for the life of me. Why would we let Nemanja go there?
"He’s been outstanding for us and you’ve seen in the short period that he’s been there [at Man Utd] how he’s allowed Pogba to basically do what he wants.
"I just couldn’t see that piece of business at all."
Selling a key player to a rival is unforgivable, especially considering the Red Devils are top of the table after three rounds.
Mourinho appears to have finally found balance and has watched from the sidelines as his team have scored ten and conceded none in their opening three matches.