The Chelsea striker spent last season under Martinez's management.
The Spaniard told El Mundo Deportivo: "Romelu is a bit like Gerard (Deulofeu), a great player, but young. He came to Liverpool still somewhat undisciplined tactically, but has improved a lot, not to mention his great technical and physical conditions.
"Everton has improved him, now he knows to get out and work on his play, to press more."
Lukaku is being linked with Atletico Madrid and Martinez says the Belgian would be a good option.
"If, indeed, he goes to Atleti, knowing the work of Diego Simeone, I'd consider him good for Atletico Madrid. Also, I think his characteristics would fit very well for Cholo and vice versa."
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