Gabriel Martinelli was born on 18 June 2001 in Guarulhos, São Paulo, Brazil. He began his football journey with Corinthians' futsal setup before moving to Ituano in 2015, where he signed his first professional contract in 2017. After scoring six goals in the 2019 Campeonato Paulista and attracting interest from several clubs, he joined Arsenal in July 2019 for a reported fee of £6 million at just 18 years old.
Martinelli made an immediate impression in north London, scoring in each of his first four starts — a feat not achieved at the club since Ian Wright. A memorable solo run against Chelsea in January 2020, covering over 60 metres to slot past the goalkeeper, was voted Arsenal's Goal of the Season by fans. He went on to win the FA Cup that same season. In the 2022–23 Premier League campaign, he finished as the club's joint-top scorer with 15 goals across all competitions, also equalling the record for the most Premier League goals by a Brazilian in a single season.
A direct, rapid left winger who favours cutting inside onto his right foot, Martinelli has become a key part of Mikel Arteta's attacking system at Arsenal, where he holds the number 11 shirt.
At international level, Martinelli won an Olympic gold medal with Brazil at the 2020 Tokyo Olympics and made his senior debut for the Seleção in March 2022, going on to represent the country at both the 2022 FIFA World Cup and the 2024 Copa América.