The Belgium international has scored just twice since he moved to Goodison Park from Chelsea on a permanent £28million deal in the summer.
At this stage 12 months ago he had twice as many goals while playing on loan for the Toffees, but Martinez believes last season's exertions followed immediately by the World Cup have taken their toll on the 21-year-old.
However, with Arouna Kone still not fit after a serious knee injury almost exactly a year ago, Steven Naismith operating better in a slightly deeper role and 33-year-old Samuel Eto'o seen as a back-up, Martinez has had little option but to keep putting his club-record signing back in the firing line.
The Spaniard admits he does not think leaving out Lukaku now will benefit him, but they will focus on getting him back to peak fitness in the next couple of weeks.
"Romelu is still finding his best moment of form," he said.
"Any player coming out of a World Cup always takes a transitional period to get their fitness back to normal.
"I think Rom has done incredibly to make himself available for the games we've had.
"Only (goalkeeper) Tim Howard has played the same amount of games and his desire to help the team has stopped him being able to concentrate on being fully fit.
"Over the next few weeks we are going to try to give him that physical element he needs, but he is a young man who will be an important player for us.
"I think Rom needs to be playing and getting his match fitness and he is too important for, us so we can't afford to give him any resting period - I don't think that would help him."
Lukaku's lack of goals and defensive lapses have contributed to a haul of just six points from seven matches which has left Everton 17th in the table - a far cry from last season when they were in or just outside the top four for three-quarters of the campaign.
Martinez accepts they have contributed to their own failings so far, but despite being much worse off position-wise than they were 12 months ago, he is not about to start re-evaluating his projections for the season.
"I still feel in the league we are still suffering from dropping four points in the two early games at Leicester and against Arsenal," he said ahead of the visit of Aston Villa.
"It is not a moment to assess where we are in the league
It is a period where we are working to get ourselves in the best possible position before we start the final third.
"We're taking every game slowly and for us the only concentration is Aston Villa.
"Villa is the last team you want to play at home
They got a very good win at Stoke - we all know how difficult it is there - and then they went to Anfield and got an impressive result there."
Aston Villa midfielder Fabian Delph could miss England's international fixtures next month amid fears he may have a serious shoulder injury.
The Three Lions rookie fell awkwardly in training on Tuesday after returning from England duty last week.
Villa boss Paul Lambert is unsure of the severity of the injury but admitted he does not know if Delph will need surgery, which would surely rule him out of England's Euro 2016 qualifier with Slovenia on November 15 and the friendly with Scotland three days later.
Lambert initially sounded optimistic - labelling Delph simply "a doubt" for Saturday's clash with Everton.
"It was here on Tuesday, he had an awkward fall so he is a doubt," he said.
"We don't know yet
We will be monitoring it in the next few days
It's his shoulder
It was an awkward fall
No-one was near him
He fell on his shoulder
It is not always straightforward so we need to go and get it checked out.
"We will need to monitor it and see what the best solution is."
However, asked whether it was a dislocated shoulder, Lambert said: "Yes, probably that
Whether it is enough to allow it to rest for a couple of weeks I don't know or if there is more to it.
"I am pretty sure the medical people will discuss that."
Lambert is unsure whether Delph will require surgery.
"That's the thing, we don't know," he said
"That will be left up to the medical people to see what is the best procedure for it."
Defender Philippe Senderos is also likely to miss the Everton match with a thigh problem.
Source : PA
Source: PA