On August 11, 2019, Gabriel Martinelli made his competitive debut for Arsenal in the Premier League against Newcastle United.
Martinelli scored his first goal for Arsenal in a 5-0 win against Nottingham Forest in the EFL Cup in 2019. He netted twice, showcasing his potential and finishing ability.
On October 3, 2019, Martinelli scored twice and provided an assist in Arsenal's 4-0 win over Standard Liège in the Europa League. His performance was lauded for its maturity.
Martinelli's most memorable moments came on January 21, 2020, when he scored a stunning solo goal against Chelsea at Stamford Bridge.
Martinelli was part of the Arsenal squad that won the FA Cup in the 2019-2020 season. His contributions throughout the campaign were significant in Arsenal's success.
On December 9, 2019, Martinelli made his first Premier League start for Arsenal against West Ham United. He scored the equalizer in a 3-1 comeback win.
In the 2020-2021 season, Martinelli scored a beautiful volley against Manchester City in the EFL Cup. Despite the team's loss, his goal was a highlight of the game.
After a lengthy spell on the sidelines due to a knee injury, Martinelli made his return to the Arsenal first team on December 19, 2020, against Everton.
Martinelli was part of the Arsenal team that won the FA Community Shield in 2020, defeating Liverpool on penalties.
On November 22, 2020, Martinelli scored a crucial goal in Arsenal's 4-2 win over Leeds United. His goal was pivotal in securing the win and highlighted his importance to the team.