United had made Haaland their top target as recently as March, amid fears the Uruguay international would leave for Boca Juniors.
But Cavani deciding to stay saw them switch focus, with the Red Devils opting to spend big on Jadon Sancho instead.
Sancho arrived from Dortmund for a fee of £73million and the Bundesliga giants are unwilling to lose Haaland in the same summer as well given his importance to the side.
Chelsea, therefore, may be wasting their time.
They do have alternatives in mind, though, with Romelu Lukaku continuing to be linked with a blockbuster move to Stamford Bridge.
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