But if a report in Wednesday's Sun is to be believed, the Red Devils will have to dig deep: the Toffees reportedly want £65 million to get their man.
The former Chelsea striker, for whom Everton paid £28m after a stellar loan spell, has banged in 19 goals (15 league, four cup) in the first half of the season, prompting interest from the likes of Real Madrid and PSG as well as Louis van Gaal's team.
Reports last week insisted that the player himself did not want to stay in the Premier League - but should Everton decide to sell, then they'll certainly want a premium on the previously-mooted £50m fee if they are giving their star man to a rival for that Europa League spot.
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A price of £65m, incidentally, would put his value at a staggering three times higher than the estimate given by Transfermarkt - despite Lukaku being just 22, and having a contract for the next three and a half years.
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For reference purposes, 27-year-old Sergio Aguero - whose contract also runs out in June 2019 - is listed at £42 million. Though that too seems very low, given the likely cost of finding a replacement who, like Aguero, comfortably sits inside a list of the world's best 10 strikers.
Lukaku, despite his good start to the season, has a lot to prove before he could claim to be in such company. £65m for a player who has never exceeded 17 goals in a league season would be extremely generous, and would make him the sixth most expensive player of all time (just ahead of prospective future team-mate Anthony Martial.
Yet there is no denying his skill and his potential. Would it be a good move or a crazy one? Vote in our poll right here:
£65M FOR ROMELU LUKAKU IS...
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