The Belgian has gone nine games without a goal and started on the bench against the Toffees as Marcus Rashford was given a central role.
Mourinho stuck by Lukaku throughout a similar drought last season and referred to the Belgian – as well as Nemanja Matic – as one of only two United players playing at a consistently high level after the clubs exit to Sevilla in the Champions League.
Much, though, has changed at Old Trafford since and United looked tellingly more vibrant in attack in Lukakus absence against Everton.
Mourinho had hoped his decision to drop Lukaku would serve as a wake-up call for the 25-year-old but Metro.co.uk can reveal the forward feels personally attacked by the decision and believes hes being made a scapegoat for the sides problems.
Lukaku feels the service from midfield and wide areas has been poor throughout the season and that the team are not playing to his strengths.
The former Everton striker is typically reserved around Uniteds training ground but the Belgian is said to have been miserable all week and his team-mates have noted his negative demeanour.
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Lukaku was not spotted as United boarded a flight on Friday to the south coast for their clash against Bournemouth and that could offer Rashford another chance to impress in his favoured position.
United face trips to Juventus and Manchester City after their game against the Cherries and will be keen to make some ground on top four rivals Arsenal and Tottenham, who face Liverpool and Wolves respectively on Saturday.