Chelsea have already secured two deals to strengthen their squad ahead of next season.
Striker Timo Werner has arrived from RB Leipzig to bolster the Blues' attack, whilst Hakim Ziyech joins from Ajax to inject some additional creativity to the midfield.
But Chelsea's end to the last campaign showed that improvements have to be made in other areas, particularly in defence.
The FA Cup final defeat to Arsenal highlighted the weaknesses that remain in Chelsea's back four and goalkeeping department, as did the admittedly more understandable, 4-1 humbling against Bayern Munich in the Champions League last-16 second leg.
Pressed on what Chelsea are planning in the transfer market, boss Frank Lampard told BT Sport after the Bayern defeat: "We will look at that.
"We have worked at it already. From having a transfer ban you feel the fact that other clubs have spent and improved and recruitment is a big part of this game.
"When you look through this team, nights like tonight in a footballing sense, show me a lot.
"The season has ended. It is a very quick turnaround but now is the time to see what areas we can improve."
It is understood Lampard is keen to add a new goalkeeper this summer, as well as a left-back.
And according to Sky Sports, Chelsea are moving closer to signing Leicester City's Ben Chilwell with developments expected 'this week'.
The report claims the England international is Lampard's number one target, with the Blues in a strong position with the offer of Champions League football and an automatic berth in the starting line-up.
It is also claimed that current Blues defender Emerson Palmieri is expected to join Inter Milan as soon as the Serie A side's Europa League campaign is over.
The Italian international signed for the Blues from Roma in a £20m deal in January 2018, but has quickly fallen out of favour at Stamford Bridge, and Inter are ready to offer the left-back a return to his homeland.
An agreement for a five-year contract is reportedly in place, with personal terms agreed.
