The Red Devils are in brilliant form heading to Merseyside following a run of six victories and one stalemate in the Premier League so far this season.
Mourinho’s men have already scored 21 goals and have kept six clean sheets to help the Red Devils keep pace with leaders Manchester City.
Manchester United haven’t faced one of their traditional rivals in the Premier League so far to raise questions about the legitimacy of their title credentials.
Manchester City, on the other hand, were 5-0 winners against 10-man Liverpool at The Etihad, although Sadio Mane’s sending off helped the Citizens’ cause.
Pep Guardiola’s men were 1-0 winners against defending Premier League champions Chelsea at Stamford Bridge in their last game before the international break.
Former Manchester United defender Neville warned Mourinho about the big challenge facing the Red Devils against Liverpool this weekend.
“It’s the first real test. I’ve seen massive improvements,” Neville told The Debate on Sky Sports on Thursday night.
“It’s whether they can improve on the biggest occasion. Going to Liverpool is the ultimate test for Manchester United.”
Manchester United are looking to win their first Premier League title since Sir Alex Ferguson led the Red Devils to their 20th top-flight crown.
The Red Devils finished in sixth place in the Premier League last term but won the EFL Cup and the Europa League.
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