The Premier League champions have signed four players this summer but the west London side are still looking lightweight ahead of a return to the Champions League.
Chelsea have brought in Manchester City goalkeeper Willy Caballero, AS Roma defender Antonio Rudiger, Monaco midfielder Tiemoue Bakayoko and Real Madrid striker Alvaro Morata.
The Blues have seen some influential players leave Stamford Bridge this summer after Nemanja Matic completed a controversial £40m move to Manchester United from Chelsea.
Club legend John Terry was also one of six players to call time on his Chelsea career and move to Championship side Aston Villa earlier this summer.
Former England and Newcastle striker Shearer explained why Chelsea still need more additions to their squad ahead of transfer deadline day.
“They have let a lot of squad players go, so even after signing Bakayoko, Antonio Rudiger and Alvaro Morata as like-for-like replacements for Matic, John Terry and Diego Costa, who looks like leaving too, they are still down numbers-wise,” Shearer told BBC Sport.
“I think Chelsea have to go out and make two or three signings in the next couple of weeks and Tottenham are in the same boat because they also need to bolster their squad.”
Chelsea won the Premier League title with two games to spare last season after finishing seven points clear of closest challengers Tottenham Hotspur in Conte’s first season in charge.
The Blues lost to Arsenal in the Community Shield last weekend following a defeat on penalties at Wembley last weekend.
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