The left-back has now returned to full training following a lengthy spell on the sidelines with a knee injury.
The Sun say Rahman is impressing Antonio Conte – and the Italian chief could draft him into the first XI.
Rahman had a loan stint at Schalke last term.
But he failed to impress and managed just 13 appearances for the Bundesliga side.
Rahman has had an underwhelming Chelsea career to date since being snapped up from Augsburg in 2015.
He’s played just 15 games for the Blues and fell off the radar during Jose Mourinho’s tenure at Stamford Bridge.
However, that could be about to change.
Conte failed to sign another left-back over the summer and Rahman could now provide competition for Marcos Alosno.
The former Juventus boss is relatively well stocked in central defensive roles, but has only limited cover on the flanks.
Andreas Christensen was brought into the first-team squad after an impressive temporary spell at Borussia Monchengladbach.
Antonio Ruddier was snapped up from Roma and right-back Davide Zappacosta was poached from Torino.
Chelsea face Leicester at the King Power Stadium this afternoon.