The Red Devils will make the short trip to Anfield in their next Premier League fixture on Saturday afternoon as Mourinho’s side look to preserve their unbeaten record.
Manchester United have racked up 19 points from their opening seven Premier League games to keep pace with leaders Manchester City at the top of the table.
Mourinho’s side have scored 21 goals and have conceded twice to underline their impressive start to the season.
Liverpool have only netted 12 times in their opening seven games as Klopp’s attack struggled to take their chances in a 1-1 draw at Newcastle United last time out.
Manchester United battled to a goalless draw with Liverpool in their Premier League meeting at Anfield last season as Mourinho adopted an overly conservative approach to the clash.
However, ex Reds captain Barnes warned Manchester United that looking opting for an attacking approach in their Premier League meeting this weekend could prove costly.
“If you go head-to-head with Liverpool rather than sitting in deep and defending in numbers to stop Mane, Salah, Firmino, you come a cropper and that is what has happened to Arsenal, Chelsea, Tottenham, Manchester United,” Barnes told talkSPORT.
“If they go all-out attack against Liverpool, which they are under pressure do because they are Man United and they are top of the league, then I think Liverpool will win.”
The Red Devils are looking to win their first Premier League title since 2013.
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