Brazilian outlet Globo Esporte, as quoted by Metro, is reporting that the north London side are keen to complete a deal to bring the 18-year-old forward to The Emirates this summer.
According to the same story, Arsenal have agreed a £6m fee with his club Ituano and will announce the signing in the coming days.
It is expected that Martinelli will become Arsenal’s first signing of the summer transfer window as Unai Emery looks to revamp his squad ahead of next season.
The same story claims that Arsenal will only have £45m to spend on new transfers this summer as Emery prepares for his second season in charge of the club.
Arsenal finished in fifth place in the Premier League table last season and missed out on Champions League qualification after they were beaten 4-1 by Chelsea FC in the Europa League final.
The north London side are expected to have a busy transfer window as Emery looks to prepare his squad for a top-four battle next term.
Arsenal have not won the Premier League title since their famous unbeaten triumph in the 2003-04 campaign.
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