Mourinho Fears Reds Backlash
The Republic of Ireland winger passed a medical on Tyneside and signed a five-year contract. And although Liverpool and Tottenham were in the race at the death, Mourinho didn't want the player to go to a side he feels could be challenging him for the Premiership, or to his near neighbours.
Duff was a £17million signing from Blackburn in 2003, and although he has been a success with the Blues (with two Premiership medals to prove it) he didn't fancy a 'bit part' at Stamford Bridge next season.
Mourinho, on the other hand, refused the offer by Liverpool, knowing full well this could be a player who could come back and haunt him.
Liverpool's loss - Newcastle's gain.