The Scottish Sun says United are eyeing £5million-rated Rangers keeper McGregor.
Old Trafford superscout Martin Ferguson, brother of boss Sir Alex, watched the Scotland No1 at Hampden on Tuesday.
McGregor, 28, pulled off a string of stunning saves in the Euro 2012 clash with world champions Spain.
And he's now on the Old Trafford radar as Fergie seeks a long-term replacement for veteran Edwin van der Sar.
McGregor's Ibrox contract runs until 2013 and Gers have offered him a new five-year deal to stay with the champs.
The keeper is in the form of his life after Champions League clean sheets at Old Trafford and against Bursaspor.