Sol Campbell: "This will hit the players hard.
"The players admired him and liked him and won't be happy now he's gone like this.
"It makes no sense.
"Here is a guy who has done an unbelievable job.
"He got the club back into the Premier League and any manager would have been rewarded for that with a new contract, but Chris wasn't.
"The players are sure to be asking themselves, 'What the hell is going on?', that is only natural.
"When we left training this morning none of the players had a clue this was coming.
"Yes, it has come as a shock, and it will affect the dressing room there is no doubt about that."
Peter Beardsley, the former Newcastle and England striker, will take over for Saturday's crunch fixture against Liverpool and be assisted by Steve Stone.