Arteta is enjoying his first managerial role at the Emirates after replacing Unai Emery at the start of the year.
The Gunners had turned a corner under the Spaniard, keeping their top-four hopes alive, until the outbreak of coronavirus stopped matches.
Speaking about his boss, Martinelli told FourFourTwo: “He’s been brilliant. He pays a lot of attention to moves and keeps pushing me to improve my game; not only in attack but defence, too.
“The boss is very wise tactically and incredibly helpful. He’s not an angry guy at all, but likes showing you exactly what to do on the pitch: ‘If the ball goes that way, don’t stay here, go there and turn your body that specific way.’ He has a keen eye for detail.”