Arsene Wenger believes Eduardo must overcome a 'psychological hurdle' if he is to make a full recovery from a badly broken leg.
The Arsenal striker has been out of action since February, but came through 45 minutes for the Gunners' reserves on Tuesday night.
The Croatia international is now hoping to back in contention for a first-team place in a fortnight's time, despite his manager's reluctance to put a timescale on his rehabilitation.
Wenger is reluctant to throw the 25-year-old back into too soon, aware that the former Dinamo Zagreb man must first dispel any fears that are plaguing his mind.
"For him to be back playing in the first team will not be a physical problem, it will be more a psychological hurdle to go back into the fight," the Frenchman told the club's official website.
"For a striker, the goal is about the fraction of a second he was ahead of the defender. Any reluctance to go into contact takes that away and then you do not score any more.
"That is where the question mark will be about Eduardo. He is a very brave guy, but sometimes you cannot master those kind of reflexes.
"In training now when he plays with us, everyone is very careful with him, because nobody wants to take responsibility of a bad tackle and he is injured.
"So it is better he goes into a game where people do not care about him and he discovers for himself he is strong enough to deal with it."
While Eduardo should expect to be called upon in the near future, Czech playmaker Tomas Rosicky remains a long-term absentee.
The 28-year-old has been sidelined since the turn of the year, unable to shake off a persistent hamstring problem.
He did undergo surgery over the summer in an effort to cure the ailment, but continues to make slow progress in his pursuit of full fitness.
"We have to assess him to see how he has progressed and he should start training slowly again this week," Wenger added.
"First it will be a build up of his strength to get him outside and run a little bit at the beginning of January if it all goes well."