Roy Keane was left unimpressed with Mourinho's latest complaints.
Pep Guardiola's side came from behind to share the points with Borussia Monchengladbach.
Webb took charge of a Champions League and a World Cup final during his career.
The former Manchester United captain believes the club needs more characters.
The Ireland assistant would 'go into the trenches' with Zlatan Ibrahimovic.
As usual, he did not hold back with his criticism.