The highly-rated 18-year-old completed a £6m switch from Ituano on Tuesday.
Most Gooners won’t know much about the Brazilian striker, but he says his game is based on the prolific Ronaldo.
“I model my game on Cristiano Ronaldo, he is a player who works hard, pushing himself to the next level. Always in the run for titles and individual trophies,” said Martinelli.
“I look up to Cristiano Ronaldo, [Lionel] Messi and Neymar as they are players who can decide games and are very professional, who dedicate themselves to the whole game.”