French outlet RMC Sport, as quoted by the Daily Mirror, is reporting that newly-appointed Arsenal scout Sven Mislintat has identified central defender Diallo as his first target since joining the Gunners from Borussia Dortmund.
The same story claims that the 21-year-old Diallo could go straight into the first team at The Emirates and that Arsenal have already made contact with Mainz ahead of a potential move.
The France Under-21 captain joined German side Mainz from Monaco in the summer transfer window and scored two goals in 15 Bundesliga appearances so far this season.
Arsenal are bound to be linked with a host of players in the coming weeks as the January transfer window draws ever nearer.
The Gunners could be on the lookout for reinforcements in the new year, especially considering that the likes of Mesut Ozil and Alexis Sanchez could be set to leave the club at the end of the season.
Arsenal were not one of the busier clubs in the summer transfer window, with Arsene Wenger having only bolstered his squad with two players following the signings of Alexandre Lacazette and Sead Kolasinac.
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