Amorim would like United to build up with a genuine three at the back, rather than the four it has been when protection is the first priority. At Anfield, United took the lead because Martinez sensed a moment to press high, snapping into Mohamed Salah to win the ball and then stay up to receive Fernandes’ slipped pass.

Ruben Amorim has warned Manchester United fans that the rest of the season is going to be a "rollercoaster." United followed up positive performances against Liverpool and Arsenal with a lacklustre display against the Premier League's bottom side Southampton on Thursday.

Manchester United are looking at Wolves’ Rayan Ait-Nouri as an alternative at left-back. Ruben Amorim has made the position a priority this January as he seeks tactical balance for his team. Paris Saint-Germain ’s Nuno Mendes is the top choice,