Chelsea manager Antonio Conte is targeting four to five signings in the summer transfer window after the Blues completed deals for goalkeeper Willy Caballero and defender Antonio Rudiger, who arrived from AS Roma.
According to the Italian publication La Gazzetta dello Sport, the Blues boss is frustrated after the west London club lost their priority transfer target Romelu Lukaku to Manchester United. The Belgium international was all but set to return to Stamford Bridge from Everton.
However, Jose Mourinho's side hijacked the deal as United completed the £75m ($98.2m) deal for Lukaku. Conte expressed his unhappiness to Chelsea technical director Michael Emenalo and Marina Granovskaia, who acts as the club owner Roman Abramovich's representative.
The Italian manager, who joined Chelsea last summer, helped the English capital club win the league in his debut season in the Premier League. They lost to Arsenal in the FA Cup final as the Gunners denied the Blues an opportunity to complete the domestic double.
Chelsea will return to the Champions League after a year's absence from the European competition. The former Juventus and Italy manager believes it is necessary for his side to bring in players with international experience in order to challenge at all fronts.
The 47-year-old has identified AS Monaco's Tiemoue Bakayoko, Borussia Dortmund star Pierre-Emerick Aubameyang, Juvenus defender Alex Sandro and Real Madrid duo of Alvaro Morata and Danilo as summer targets. Conte wants Chelsea to help him complete these signings.
Bakayoko is already in London for his medical and the French international is expected to complete his move to Stamford Bridge. Sandro, who plays as a left-back for Juventus and the Brazil international's compatriot and right-back Danilo are targeted to strengthen Chelsea's defence.
Conte has already informed striker Diego Costa that he is no longer included in his plans at the club. The Brazil-born Spain international is not part of the Blues' pre-season squad as the club continue to search for a new striker.
Aubameyang has been identified as a target for the English champions. However, Dortmund's former manager Jurgen Klopp is also interested in reuniting with the Gabon international at Liverpool, reports the Sun. Dortmund star is expected to cost around £65m ($85.1m) in the transfer market.
Conte wants to further strengthen his strike force and is still keen on Real's Morata, who was wanted by Mourinho before United landed Lukaku. However, the Spain international is not willing to move to Chelsea as he does not see the Blues as an option after his dream move to Old Trafford collapsed.
Morata scored 20 goals across all competitions for Real last season. Aubameyang was impressive for the Bundesliga outfit, managing 40 goals in all competitions. Should Chelsea manage to land the duo, they will have an attacking partnership of two players, who collectively scored 60 goals last term.