The person spoke on condition of anonymity Monday because the deal has not been announced. Brown already has a locker at the Raiders facility and has been given uniform No. 19 but the team hasn't announced the signing. ESPN first reported the deal.
Brown had 60 catches for 801 yards and three touchdowns in 30 games with San Diego in 2011 and `13. He missed the 2012 season with a broken left ankle.
Brown missed most of training camp this season with a sore calf and was released earlier this month.
The Raiders waived linebacker Bojay Filimoeatu.
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