Gabriel Magalhaes has signed a new, long-term contract with Arsenal.
It is understood the central defender finalised terms on Friday, following a meeting between manager Mikel Arteta and his representatives.
Arsenal hope it will be the first of a flurry of contract extensions involving key players, with the club working to tie down Bukayo Saka, William Saliba and Gabriel Martinelli, too.
Magalhaes has started every Premier League game this season, forming a promising partnership with Saliba.
Only Newcastle have conceded fewer league goals than Arsenal (10), who sit four points clear atop the table.