Romeo Lavia and Deivid Washington will both complete medicals at Chelsea on Wednesday.
Belgium midfielder Lavia is due at Cobham after a £53million deal was agreed with Southampton on Tuesday night, with a further £5m potentially payable in add-ons.
Santos striker Washington, meanwhile, will cost an initial £13m with another £4m possibly due in add-ons and he is expected to sign a six-year contract at Stamford Bridge.
Chelsea will now weigh up whether or not to send the Brazilian teenager on loan to Ligue 1 club Strasbourg, who are part of a newly-built multi-club model under parent company BlueCo.
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Lavia, though, is certain to remain part of Mauricio Pochettino’s first-team squad this season as business accelerates in west London following a £115m British-transfer record move for Brighton midfielder Moises Caicedo.
Chelsea have also triggered the £35m release clause for Crystal Palace winger Michael Olise.
Personal terms are considered a formality and the 21-year-old is expected to join the club in the coming days if he can pass a medical.
Olise is currently expected to be out until September after tearing his hamstring at the Under-21 European Championship with France over the summer.
