The Argentina star has been recovering from a hamstring injury in his homeland and has not featured for the Catalan club since a 4-1 victory over Real Betis on November 10.
However, Barca confirmed Messi's return to training on Thursday, and hopes will be raised that he will be available to play some part in Sunday's Liga clash with Elche, with Fabregas expecting the attacker to come out fighting.
"He definitely needed to rest physically because he had already suffered this (injury) and there was no other option than to stop playing," Fabregas told Marca.
"He had four or five injuries in a row in a muscle that he uses a lot in accelerating from a standstill, which is what sets him apart.
"He had to stop no matter what and he'll be like a bull when he is back."
Messi's absence has increased the pressure on the performances of Neymar, but Fabregas feels the 21-year-old is finding his feet at the club.
"Scoring is all about streaks," he continued. "Right now the goals are going in for Neymar and that will give him a bit more confidence, stability and composure in the penalty area.
"As time passes his importance to the team will increase. He is 21 and he will develop from game to game.
"The confidence will make him a better player."
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