After Blues winger again stars while on loan at Fiorentina, we take a look at the others impressing in Chelsea's bloated squad.
Manuel Pellegrini's fixed expression of horror has good cause - if he's found this season's Chelsea a rampaging force, impossible to stop, then the future only looks bleaker for title rivals Manchester City.
While utterly dominating the Premier League this term, Jose Mourinho's squad will have plenty of reinforcements to be bolstered with in the summer, as their fleet of loan players return to West London.
Many won't get a look in at Stamford Bridge, and will be moved on to generate funds for a marquee signing or two - with Chelsea notoriously good at maximising sales potential of unwanted fringe players. David Luiz, anyone?
After Mohamed Salah notched both goals as loan side Fiorentina beat Juventus 2-1 on Thursday - taking him to six goals in six games since arriving as part of the deal that secured Juan Cuadrado's signature - here we offer a verdict on Chelsea's loan contingent, and what Mourinho should do with them at the end of the season.
Hopelessly inept against League One Bradford, but mesmerising as he tears apart Serie A champions Juventus, the 22-year-old's inconsistency won't do for as demanding a boss as Mourinho.
But his talent shouldn't be written off just yet, either, as his form in Florence shows.
However, his flying start at the Viola could trigger a lucrative offer to let the Egyptian remain in Tuscany permanently. With no obvious first-team berth for him back in London, Mourinho could be tempted to cash out on Salah.
Verdict: Keep, unless a serious bid is received.
Signed as part of Chelsea's buy-bye plan - buy talent, then send them off on loan for several seasons - Omeruo has impressed at Middlesborough this term.
The Nigeria international, 21, was purchased by the Blues in 2012, and has been patiently waiting for his chance to step up.
With serious questions marks against the future of Gary Cahill, an underwhelming debut season from Kurt Zouma, while John Terry can only go on for so long, back-line reinforcement is a priority.
Unless they can persuade Real Madrid to release long-term Mourinho target Raphael Varane, or win the congested race for Mats Hummels, Omeruo could be worth a shot.
His one obstacle could be the permanent promotion of Nathan Ake to Chelsea's first team this season, suggesting the Dutchman is next in line for a shot at becoming Terry's successor.
Verdict: Use as first-team back-up, unless stellar signing arrives.
At the start of last season, Czech centre-half Kalas was given a chance by Mourinho to prove his worth, after being told to stay with the club to fight for a first-team place.
Clearly, he didn't battle enough, as he was granted just four first team appearances, before being shipped out to FC Koln, where he managed just two reserve game run-outs.
In the January transfer window, he joined Omeruo at Middlesborough, offering cover to first-choice Damia Albella.
Signed for a reported £5million five years ago, his progress has stalled, and needs regular minutes to get back on track.
Verdict: Move on for his own good.
Snared from Barcelona's seemingly never-ending fountain of youth four years ago, landing almost directly into the first team, it's surprising that Romeu has found himself sidelined recently.
Having been part of the successful Champions League and Europa League squads between 2011 and 2013, Romeu was sent to Valencia last season and Stuttgart this after Mourinho's return to the club.
However, he was given a new three-year deal before going to Germany, and a player with his pedigree must surely hold out some hope of making the grade.
With his 24th birthday looming in September, Romeu isn't quite done - but will view next season as crucial, with doubts about Ramires and John Obi Mikel.
Verdict: Add to first team squad.
German winger Marko Marin was offloaded to Anderlecht in January, giving the Belgian giants an option to sign permanently in the summer, while Thorgan Hazard's loan at Monchengladbach will become a full sale, with Chelsea retaining a buy-back clause.
Victor Moses is clearly unwanted, in the midst of a second loan spell with divisional rivals, while Patrick Bamford's impressive stint at Middlesborough has put him in the shop window for a Premier League loan next season.
Josh McEachran is in his fifth loan spell since signing for Chelsea, currently with Dutch side Vitesse, where he has again failed to establish himself - the 22-year-old becoming a regular in just one of his temporary stints, and even less likely to for the Blues.
Marco Van Ginkel has been riddled with injuries at AC Milan, Christian Atsu can't get a game at Everton, and Ulises Davila has just pitched up in Portugal with Vitoria. All three will be available one way or another in the summer.