The Belgian pair are on loan this season and excelling elsewhere, but could they be growing increasingly disconnected with their parent club?
Despite the star-studded squad at Jose Mourinho’s disposal, Chelsea have some excellent players currently on loan away from the club.
Although the Blues have allowed them to leave temporarily as a way of ensuring the duo get regular first-team football, are they risking the players not wanting to come back to Stamford Bridge?
Courtois has been on loan at the Vicente Calderon for the last three seasons, and has grown into one of the most respected and able stoppers in the Spanish game.
With Petr Cech in the Chelsea side at the moment and looking as solid as ever, the west London side have to consider just how and when Courtois will get his chance in the Blues’ first-team.
At the end of this term, Chelsea will need to decide whether to install Courtois as the first-choice, demoting Cech, or to continue with the more experienced goalkeeper in the first-team.
With rumours that Courtois is keen to remain at Atletico in the long-term and that Barcelona may well even be considering a move for him, Chelsea need to play the situation delicately or risk losing the star.
He will surely be unwilling to sit on the Stamford Bridge bench, and the longer he stays away from west London, the more likely it is that he will want to play permanently for Atletico or another club.
Chelsea also risk running Courtois down to the last year of his contract, where the goalkeeper will have more power in dictating his future.
Lukaku has proven himself as one of the most devastating young strikers in European football, and it is something of a mystery that Mourinho allowed the forward to leave Stamford Bridge this season.
Similarly to Courtois, Chelsea must be careful not to ostracise or alienate Lukaku, as he may well decide that he has not been given a fair crack of the whip at Stamford Bridge and look to move elsewhere.
With rumours that Chelsea are in the market for another top-quality forward in the January transfer market, Lukaku could find himself further down the pecking order and look to secure a move away from the London club.
With Courtois and Lukaku having the ability to be some of the best in their positions in the English game, Chelsea must ensure that they show them the required love and attention to ensure they do not want to pursue challenges elsewhere.
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