The 21-year-old has been deemed surplus to requirements by the Chelsea boss, despite proving prolific in front of goal in loan spells with both West Brom and his new club Everton.Jose Mourinho has transformed strikers' careers. He turned Diego Milito from a Genoa forward into the man who decided the Champions League final. He reinvented Samuel Eto'o as a scorer who would willingly shield his right back if it meant winning the treble. He converted Didier Drogba into Europe's most feared target man. He even inspired lasting affection from the temperamental Zlatan Ibrahimovic, despite selling him.
MORE: Biggest summer transfers | Soccer's beautiful fans
It is fair to say Romelu Lukaku is unlikely to join that distinguished quartet among the forwards in Mourinho's fan club. In theory a catalytic manager and a hugely gifted attacker ought to have combined profitably for both and, in particular, for Chelsea. In practice, it seems, their relationship was over when it had barely begun.
The confirmation Lukaku is off to Everton brings a permanent parting of the ways. The reality is they separated last September, 72 hours after the Belgian missed his penalty in the European Super Cup shootout against Bayern Munich. Lukaku never did score for Chelsea. He may have deprived Mourinho of a trophy then.
As a more pertinent piece of silverware eluded the Portuguese, the decision to loan out Lukaku appeared more costly. As Manchester City won the league, as Mourinho lamented his lack of strikers, as Chelsea drew costly blanks against the comparative minnows of West Ham, Aston Villa, Crystal Palace and Norwich in the final four months of last season, the feeling was that the Blues could have benefited from the presence of Lukaku.
Not that Mourinho appears to concur. Unapologetic, unrepentant, unwilling to change course, the sense is he didn't give Lukaku a chance. The irony is that he signaled the 21-year-old's departure by re-signing his role model, Drogba. They may be deemed too similar to co-exist at a club.
The chances are that Lukaku is not sorry to leave. His comments over the past 12 months have hinted at his impatience. Instead, his regret may be that he can't complete his apprenticeship under his idol.
In an interview last year, he said he particularly admired "Drogba's hold-up play, which is still unmatched." It offers an insight into why Mourinho has deemed him surplus to requirements. It is one area where the 'Baby Drogba' differs from the aging original.
Lukaku has the pace on the counterattack that ought to appeal to Mourinho, but he isn't quite the same outlet, bringing others into play, and allowing a team to play through him.
The Chelsea manager likes his strikers to be warriors. While Lukaku has the physique of Drogba, he doesn't have the physicality. He won't bash into and batter defenders the way the Ivorian and another striking signing, Diego Costa, will.
But there is another significant difference: Lukaku is more prolific. In Drogba's last season at Stamford Bridge, he only mustered five league goals. Last season, Mourinho's blunt strike force of Eto'o, Fernando Torres and Demba Ba only mustered 19 between them. Lukaku managed 15 on his own. The more ruthless Costa ought to top that tally but, if he is injured, Torres and Drogba probably won't.
The numbers highlight Lukaku's talent. He has scored 65 league goals by the age of 21; perhaps more pertinently, only Robin van Persie and Luis Suarez have topped his tally of 32 in the last two Premier League seasons. The logical conclusion is that goals alone are not enough for Mourinho.
His barbed comments last December, when he suggested Lukaku knew precisely why he had been exiled to Everton, were instructive. "Romelu likes to speak," he said. "He's a young boy who likes to speak. But the only thing he didn't say is why he went to Everton on loan.
"That's the only thing he never says. And my last contact with him was to tell him exactly that. It's something he should say, the reason why he's not with Chelsea and is in Everton."
The loquacious Lukaku is too independent-minded for Mourinho's liking (and, at times, for Belgium coach Marc Wilmots too). The chatty, permissive Roberto Martinez has fewer problems with that approach.
Lukaku studies strikers - Drogba included - and games on DVDs. Mourinho prefers players who absorb his instructions, rather than embarking on their own individual quest for knowledge and self-betterment. His teams are not a democracy but a (sometimes) benevolent dictatorship. Mourinho has long succeeded by persuading gifted players to sacrifice themselves for the greater good.
There is a theory at Chelsea that Lukaku, eyeing up first-team football, wasn't willing to commit to the cause by fighting for his place. Yet his loan spell at West Brom showed Lukaku was the most potent of impact substitutes. However single-minded he may be, he does not need to be in the starting XI to make his mark.
That, perhaps, is the most surprising element of his inability to make a mark under Mourinho. Lukaku can prosper against tiring defences. He does so more consistently than Drogba or Torres; men from older generations.
Yet his youth helps explain his price tag. In the era of Financial Fair Play, Lukaku, like David Luiz, is a player Mourinho was willing to sacrifice to fund his rebuilding. Both are perhaps too individualistic for Mourinho's taste.
Instead, he concluded their value was on the balance sheet and sold them. They were expensive, but expendable.