The Daily Star says Fabregas was a target for David Moyes - Dutch boss Van Gaal's predecessor - and United failed to prise him away from Barcelona a year ago.
But when Fab became available at Barcelona, Van Gaal made it clear to United chief executive Ed Woodward that he did not want him.
Dutch boss Van Gaal believes United already have a similar player to Fabregas in his Spain team-mate Juan Mata.
That left the field clear for Chelsea to bring back the midfielder, 27, to the Premier League.
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