Everton manager Ronald Koeman has suggested that Romelu Lukaku was almost impossible to replace at Everton this summer.
Lukaku had been at the Toffees for the previous four seasons, before moving to Manchester United this summer for £75m and has seemingly left a huge void in quality in Everton's front-line.
The reason for this being that the Belgium international had scored 25 league goals last season for Everton, while the Toffees currently struggle for goals in his absence.
Koeman, whose team have made a slow start to the campaign and visit United this afternoon, with Lukaku in fine form after bagging six goals in six games, realised that replacing the 24-year-old was always going to be a huge task:
"I don't say impossible but that was close to impossible to get someone in who will score that amount of goals that Romelu scored for Everton," said Koeman to the Liverpool Echo.
"With Romelu we had enough fights about how he needs to press, how he needs to run, how he needs to move but in the box, with opportunities to score, he is one of the best."
"It is always difficult to replace players like him because of the person he was, the physical boy that he is, the number of goals that he scored. It is difficult."
Everton made a number of attacking signings this summer, using the £75m received for Lukaku, by adding the likes of Wayne Rooney, Davy Klaassen, Sandro Ramirez and most expensively, Gylfi Sigurdsson for £50m.
However, the Toffees have scored just two goals in their opening four league games, while taking just four points, which sees them struggling towards the wrong end of the table.
Lukaku will face his old side this afternoon, while Everton will be trying to recover after suffering back to back 3-0 defeats to Tottenham and then Atalanta in the Europa League on Thursday.