Slimani was brought to Newcastle from Leicester City in the January transfer window, but he has not featured yet.
The Algerian international has been ruled out with injury, but he is now edging closer to full health.
Slimani has been taken to Spain with Newcastle for warm weather training, and has now joined up with the Algeria squad for their upcoming friendlies over the international break.
The target-man could now be available for Newcastle’s next match against Huddersfield Town in two weekends’ time.
But Benitez has suggested that Slimani will not automatically break into his starting line-up.
“If they are doing well, he (Slimani) has to be better than them,” Benitez said.
“It’s not as if he will come and go straight (into the team) and make the difference.
“The others are doing well, and he has to compete with them. It’s positive, because we have more competition in one position.”
Newcastle’s strikers have been in better form of late, so it could be difficult for Slimani.
Dwight Gayle has two goals and two assists in his last four matches, and Ayoze Perez has proved a solid second striker.
Slimani could now be used sparingly, with Newcastle winning their last match 3-0 against Southampton.
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