Simeone acknowledges the striker has struggled for form so far this season.
He said, "For a forward, it is worrisome when he fails to meet situations that bring him closer to being able to score.
"We are working with Diego on what he feels and on what we see in where he has to improve.
"It's one more important challenge beyond the group that helps the team a lot, fixing a situation that is not usual for a player like him."
He added: "LaLiga is showing that there is no easy game for anyone and we are all on a construction road."