Mourinho praised Rafa Benitez's side for "fighting like animals" to hang on to the win.
But a season of unimaginative performances and the knowledge that they have a troublingly soft underbelly - not something you'd say of United or Mourinho teams in years gone by - gave confidence to a side threatened by relegation.
"Yes they were. But sometimes you attract that with your state of find and they fought for their lives and that is a lovely thing in football".
"Could he come in my direction in the way I think football and the way I like my players to be?"
Mourinho added: 'I am disappointed with the defending. We did more than enough to leave without a defeat.
Mourinho controversially benched Paul Pogba after the goal and deployed Michael Carrick but the strategic substitution proved fruitless. Anthony Martial was shunted out to the right, a position that has never suited him, and with Sanchez driving into the centre, Romelu Lukaku was often shoved into deeper areas, from where he actually linked play reasonably well. We missed the challenge in the air.
Newcastle had fallen into the bottom three before kickoff after Huddersfield Town's earlier win, but it responded with a vibrant display capped by Ritchie's 65th minute effort. I have to be disappointed.
"He has super individual ability - there is much to admire about his technique when he is on the ball and his general athleticism", Souness said of the player who joined United for a then-world-record £93.25m fee.
"They fought like animals and I mean that as a compliment", he told Sky Sports.
'The team cares. They have some limitations but they work hard and won't give up'. "But sometimes you attract that luck with your state of mind and at 1-0, the Newcastle players fought for their lives and I think that's a lovely thing in football". "We got lucky with some shots, but we showed the character, the commitment and the desire today".
"They've normally had good players, normally good managers". That night was an exercise in damage limitation and, to a point it worked, in that they only lost 1-0.
"My verdict is that we could've been here for 10 hours and not scored a goal".