Further terms of the contract are unknown.
The 25-year-old receiver visited with the Giants on Friday, as the team is looking to fill out its receiving corps. Victor Cruz is a restricted free agent -- Cruz would like to stay -- but New York will likely lose Ramses Barden and Domenik Hixon to free agency.
Murphy was drafted in the fourth round of the 2009 draft by Oakland, where he stayed for three seasons. He spent last year with the Panthers, playing in all 16 games and catching 25 passes for 336 yards and a touchdown.
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