Martinelli wants Arsenal to 'kick on' after ending Man City barren run
Martinelli came off the bench to score the winner in a 1-0 victory and inflict back-to-back league defeats on City for the first time in five years.
Pep Guardiola's men usurped Arsenal in the second half of last season on their way to winning the treble of Premier League, FA Cup and Champions League.
Victory lifts Arsenal above City into second in the table and level on points with leaders Tottenham.
"We know our potential and how tough it is to play against them. Today we beat them and it gives us more confidence to kick on," said Martinelli.
The Brazilian had been rushed back from injury to take his place on the bench with Arsenal missing Bukayo Saka for the first time in a Premier League game since May 2021.
"I just tried to give my best to my recovery and try to be ready for the next game," added Martinelli.
"Luckily it was for this game and I helped the team. I am happy with my goal and fitness."
City midfielder Bernardo Silva was deployed in an unfamiliar holding midfield role as he deputised for the suspended Rodri.
The Portuguese international played down the impact of City's mini slump in form, but warned his teammates about slacking off in the intensity of their pressing.
"It's a setback but it's still the beginning. We're far away from the end of the season," said Silva.
"At the end it's a game decided in a detail - a deflection.
"We gave them too much time. We have to be a bit more intense in the way we press in those moments."