Conor Gallagher, Trevoh Chalobah, Ian Maatsen and Armando Broja could be sold if Chelsea received acceptable offers this summer.
Gallagher and Chalobah, both 24, were significant parts of former manager Mauricio Pochettino’s plans, and he was ready to advocate for the duo to stay but his departure has added further uncertainty about their futures.
The Argentine left Stamford Bridge in an amicable exit by mutual consent on Tuesday evening.
Chelsea are believed to value Gallagher at around £50m as he enters the last year of his contract next month.
Gallagher remains reluctant to move despite Pochettino’s departure after a successful season, in which he often wore the captain’s armband, and made the most appearances.
The England midfielder is also cautious about rushing a move through before the European Championship this summer after being called up to Gareth Southgate’s preliminary squad.
Chalobah is also in no rush to leave with four years remaining on his contract in west London.
He was previously valued at £25m when Chelsea accepted an offer from Nottingham Forest last summer – only for him to reject a move to the East Midlands.
The English defender would only entertain offers from top seven Premier League clubs or Champions League clubs in Europe.
Left-back Maatsen, who is preparing for the Champions League final while on loan at Borussia Dortmund, is also up for sale.
The Netherlands Under-21 international, 22, extended his Chelsea contract before joining the German giants on loan in January but it included a £35m release clause.
Albania striker Broja, 22, who endured an unsuccessful loan spell at Fulham this season, is also available for sale and is attracting interest from a host of European clubs.
The two loanees are willing to move before 30 June which could help Chelsea adhere to Premier League profit and sustainability rules (PSR).
Chelsea have spent more than £1bn on transfers in the past four transfer windows – albeit while also selling £400m worth of talent – and want to continue investing in the playing squad.
However, the club deny any activity is in relation to concerns of PSR sanctions for falling foul of financial rules.
The Blues have agreed a £29.1m fee to sign 17-year-old Palmeiras winger Estevao Willian but he will only join the club in 2025 after turning 18.