David Luiz has agreed a new one-year deal with Arsenal, SportsMail reports.
His team-mate, Cedric Soares, has also agreed a four-year contract with the Gunners, despite not making a single appearance since his loan move from Southampton.
Luiz came under heavy criticism for his error-strewn cameo performance in the 3-0 defeat at Manchester City last Wednesday.
The Brazilian was at fault for the first two goals and was sent off after only 26 minutes on the pitch.
It led to many believing that his Arsenal career would be over, with his deal to expire June 30.
Clubs had until Tuesday night to finalise short-term extensions to run to the end of this season and Arsenal decided to negotiate a longer deal for Luiz to keep him until 2021.
Defender Pablo Mari, who is out for up to four months with ankle ligament damage, has also joined on a permanent deal from Flamengo.
The fee for the 26-year-old Mari is around £14m.