The Red Devils emerged with three points from a dramatic Manchester derby at the Etihad Stadium on Saturday afternoon.
Manchester City surged into a 2-0 lead courtesy of goals from Vincent Kompany and Ilkay Gundogan in the opening 45 minutes.
However, Manchester United rallied in the second half after Paul Pogba scored two quick-fire goals on Eastlands to level up the derby clash.
England international Chris Smalling netted a dramatic winner to complete Manchester United’s comeback and deny Manchester City the title.
Mourinho has won the FA Cup and the Europa League since taking over the reins at Old Trafford, while the Portuguese coach won three Premier League titles with Chelsea FC.
Former Liverpool FC captain Souness insisted that he never doubted Mourinho’s quality as a manager despite an inconsistent season for the Red Devils.
“They dig results out, they are not a great watch a lot of the time though I don’t think any of us have accused them of being a bad team or Mourinho of being a bad manager,” Mourinho told Sky Sports.
“Every manager would love his CV. They have not been a great watch at times and that is where the criticism has come from.
“They are a very effective team, but I disagree with Mourinho when he said they were controlling the game in the first 15 minutes. City could have gone in at half-time 5-0 up and it would have been a very different outcome, but they didn’t.”
The Portuguese head coach has won the Champions League with FC Porto and Inter Milan.
Mourinho has also got his hands on two Serie A titles, the La Liga crown, the Copa del Rey, the Coppa Italia and the FA Cup.
Manchester United haven’t won the Premier League title since 2013.
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