The Blues are confident that they have the ability to hold on to both loan stars without contravening their FIFA-imposed embargo on bringing in new players, with football's governing body having turned down the Premier League outfit's appeal to delay the ban.
Chelsea have taken the next step in trying to overturn and suspend the sanction by appealing to the Court of Arbitration for Sport (CAS) and could hear back shortly before the Europa League final in May 29.
They have, however, seen the Premier League transfer window reopen on Thursday without the ability to sign players.
Maurizio Sarri wants to retain both Kovacic and Higuain – despite concerns over the latter's form – and the pair are understood to be keen on staying having fallen out of favour at their parent clubs.
In Kovacic's case, a move is already being explored and a fee could be agreed to convert his current loan into a permanent deal without a need for Chelsea to re-register the player on the electronic TMS system used to process transfers.
However, Sarri's future at Stamford Bridge is far from secure, slowing the club's operations in the transfer market.
Sarri's future would have more of an effect on any deal for Higuain, as many at the club remain unconvinced by the striker, who has bagged only five goals since joining in January.
One other positive is Chelsea's ability to recall loanees such as Michy Batshuayi and Tammy Abraham, who have been plying their trade at Crystal Palace and Aston Villa, respectively, even if a ban does end up being fully imposed this summer.
Alvaro Morata, meanwhile, will not be able to be recalled from his loan at Atletico Madrid.
Ruben Loftus-Cheek's recent Achilles injury will likely see the England midfielder out for between five to nine months, leaving the club more in need of securing Kovacic for the long term.
*Additional reporting from Romeo Agresti.