The timing of the move is critical for Newcastle, who face a daunting Premier League opener against Liverpool on August 23 without a fit senior right-back. Tino Livramento remains sidelined following a minor calf operation in June, while Lewis Miley is still building up fitness after a broken leg.
If an agreement is reached with Benfica in time, Dedic is expected to go straight into the starting XI against the Reds. With Livramento not anticipated back until the end of the month, the Bosnian defender would be thrown straight into the deep end at St James' Park.