The winger impressed in trials with Barca in January and has been informed that he will be offered a contract when he turns 18 in December.
Diarra is tied to the Africa Foot Academy in Mali and spent over a month with Barca before his work permit expired in February, meaning he had to return home.
However, Barca have kept in contact and Sport says Diarra has now been told he will be signed in the January market.
Club sources have confirmed that Diarra stood out in trials, especially for his mobility and speed in all types of actions. An eminently offensive and vertical footballer, he is considered an important bet in the short and medium term.
Diarra will initially be registered with Barca Atletic for the second half of this season.
