The Costa Rica international was linked with a late switch to the Portuguese club as Arsenal bolstered their attacking options with the signing of Danny Welbeck from Manchester United.
But if he is not in his plans, then why not allow him to leave?
And the 22-year-old’s representative cannot understand why his client was not allowed to leave Emirates Stadium.
“Benfica fought until the last minute to sign Campbell but the move didn’t happen because, in the last hour, Arsenal decided to keep him,” Campbell’s agent Joaquim Batica told O Jogo.
“Wenger says he did not want to sell him. But if he is not in his plans, then why not allow him to leave?”
Campbell, who joined the Gunners in 2011, returned to Arsenal this summer after a loan spell at Olympiakos last season.
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