The striker netted a treble in Sunday's league encounter to help his side to the full three points and his coach feels he still has room for improvement
The 23-year-old netted a hat-trick at the Stadio Sant'Elia to take his league tally for 2013-14 to 13 goals in 18 appearances and Garcia believes the Italy international has the potential to get even better.
"Mattia missed the start of the season due to injury, so we can say that he has played only half a season," Garcia said at a press conference.
"He is a very complete attacker and has shown just that. He always gives his all on the pitch and always shows a great desire to win.
"I am convinced that he can still get better, though. He can switch positions with [Francesco] Totti and he has the quality to threaten even from outside the area."
Destro missed the first few months of the season due to a knee injury, but has developed into a key player at Roma since his comeback, helping them to second place in the Serie A table with his goals.