The defender was photographed with Edu, Arsenal's technical director, at Rio de Janeiro airport on Friday night ahead of his flight to London.
Arsenal hope to wrap up a deal imminently, with the defender expected to undergo a medical over the weekend in London.
The report says Arsenal will have the option to make the move permanent at the end of the season if the loan works out but the Daily Mail suggests it could be a permanent switch this month after we agreed a £7.5m deal.
The 26-year old had a series of loans while at City with Girona, NAC Breda and Alaves.
Mari, 26, is a former Manchester City defender who joined Flamengo in July past year.
The Spaniard played against Liverpool in the World Club Championships and is now poised to link up with former City coach Mikel Arteta at Arsenal.
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French health authorities have confirmed three cases of novel coronavirus (2019-nCoV) virus in France since January 24, 2020. The number of confirmed cases in China stands at 1,287. "We see how hard it is in today's world to close the frontiers".
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It should be noted that Nearby Sharing is expected to work on many different Android devices, not just Google Pixel models. Both devices should have the Nearby Sharing feature enabled, and the recipient must accept the files receipt.
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He rejected those runoff outright, saying that there was an agreement between Pakistan and Bangladesh regarding the Asia Cup. It was exclusively the final T20 sequence in 2012 when India and Pakistan clashed.
And Mari played a big part in both successes, featuring 22 times in the league and five times in the Libertadores run - including the full 90 minutes in the final.
Speaking on Friday, Arteta was asked about the chances of Arsenal bringing anyone in before the end of this month's transfer deadline.
Arsenal are set to be without Calum Chambers for the majority of 2020 after he suffered an anterior cruciate ligament injury.
However, Arteta has responded to these claims and is adamant the forward is happy at Arsenal, insisting the striker is not looking to leave.
At the moment, I am 50:50 [over signing anyone] because this transfer window is very, very complicated.
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