Arsenal manager Mikel Arteta blocked technical director Edu from signing Emerson Royal.
The Gunners were reportedly close to signing the Brazilian right-back from Barcelona.
Emerson instead joined north London rivals Tottenham Hotspur for £26m.
According to The Guardian, Arsenal were frontrunners to sign Emerson but Arteta ordered the club to pull out of negotiations.
Arteta’s hunch about Emerson has since proven correct as the 23-year-old has failed to acclimatise to Premier League football.
Edu instead signed Takehiro Tomiyasu from Bologna to play at right-back.
The Japan international has been one of Arsenal’s most impressive players this season.