The 22-year-old struggled earlier in his career, first at Chelsea and then on loan at Blackburn. However, with one season at Wigan under his belt, the Latics boss believes Di Santo is set to make a name for himself.
"He has a real focus," Martinez said. "He wants to be someone very special for Wigan and play for Argentina. He is playing with that determination.
"You do not get many as strong as him with a fantastic first touch and who run all day, with two good feet, good in the air and a goal-scoring ability.
"The technical tactical and physical aspects do not matter if you are not on song psychologically, and Franco has been a real example of how to prepare yourself."
Di Santo has scored three goals in five league appearances for Wigan this season.