Sterling, 30, was reluctant to join either Champions League sides Juventus or Bayer Leverkusen this summer. His reasoning was he wanted to join another London club to remain close to his family.
He spent last season on loan at Arsenal but the Gunners had no interest in making his loan move permanent. There were no offers from Fulham, Crystal Palace or West Ham despite encouragement from Chelsea, and his club-high £325,000-per-week wages were likely to have proved a major stumbling block.
Meanwhile, Disasi, 27 had strong interest from Sunderland, Bournemouth and West Ham but all three moves collapsed as he held out for a return to former club Monaco that never materialised.
Disasi, who spent the second half of last season on loan at Aston Villa, said in an interview with YouTube channel Carre he was fit and available to play if called upon.
Sterling, Disasi and striker David Datro Fofana were registered in Chelsea’s Premier League squad which was announced on Friday.
Maresca also ruled out Romeo Lavia and Benoit Badiashile as the duo remain sidelined alongside long-term injured trio Liam Delap, Levi Colwill and Dario Essugo.
England forward Cole Palmer remains a doubt for the trip to the Brentford Community Stadium with a groin issue.
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