#3 Selling Nemanja Matic to Manchester United
Though Chelsea failed to bring in the players that Conte would have wanted, they did spend a lot of money buying quality talents in Alvaro Morata, Tiemoue Bakayoko, and Antonio Rudiger.
They haven't exactly set the world on fire but they settled into the team very well in 5 months and provided Conte with many new options to work with.
The one transfer that hurt Chelsea the most though was the transfer of Nemanja Matic to Manchester United of all teams. Upon seeing that Bakayoko's arrival would be the end of his time at Chelsea eventually, Matic decided to get back to his favorite manager, Jose Mourinho.
This transfer went through despite the objections of Conte who wanted Matic to stay around and help Bakayoko's bedding in. In an interview, the Italian tactician said:
"Matic knows very well what I think about him"
“The importance for me about this player, who is a really good player, a top player, very important for our team, but sometimes you must accept this crazy transfer market.
"And sometimes you must accept different decisions. But he is a great loss for us."
Chelsea's decision to let him go would come back to bite them as they strengthened a direct rival who capitulated on the situation and went on a winning spree (although that has halted now). It left a huge hole in central midfield which had to be covered by a young and inexperienced Bakayoko, especially at the start of the season when N'Golo Kante was injured.
It took about 4 months and a formation change to find a stop-gap solution for the team and though it looks balanced now with the addition of Danny Drinkwater, they still lack the composure and, the solidity that Matic brought to the team.