The Red Devils recently appointed Amorim as their new head coach, replacing Erik ten Hag, who had a disappointing start to the season.
The 39-year-old comes with a big reputation of working with young talents and he is expected to give more importance to the academy at United.
M.E.N claim that the progress of Mantato is bound to catch the eye of the Portuguese and he could be promoted to the first-team in the near future.
The teenager started his career as a left-back, but he has developed into a right-winger, following a similar path as Arsenal star Bukayo Saka.
He has already chipped in with seven goal contributions this term. His strong defensive and attacking attributes could impress Amorim.
Bendito has been tipped to compete for both wing-back roles in a 3-4-2-1 formation. It remains to be seen whether he makes his debut this term.
