Marouane Fellaini (top) and Leighton Baines tackle Real Madrid's Mezut Ozil in Los Angeles on August 3, 2013.
(AFP/Frederic J. Brown)
Former Everton manager David Moyes lodged a £28 million (US$44 million, 33 million euros) bid to bring the pair to Old Trafford, including £16 million for Fellaini, the BBC and other media reported.
A £23.5 million release clause in Fellaini's contract expired at the end of July.
The Premier League champions are believed to have offered the same amount for 28-year-old Baines -- £12 million -- that they bid in June when the offer was flatly rejected.
The BBC website said Everton had greeted the new bid for Baines with anger.
Everton claim Moyes made an unwritten pact with the club not to try to sign their players when he left in the summer to succeed Alex Ferguson.
Moyes signed both players for Everton, paying Wigan £6 million for Baines in August 2007 and signing the lanky Fellaini for a then club record £15m from Belgian club Standard Liege in September 2008.
Moyes has been frustrated in the transfer market with attempts to bring Barcelona midfielder Cesc Fabregas to United so far proving unsuccessful, while England striker Wayne Rooney appears to want to leave Old Trafford for Chelsea.
United crushed Swansea 4-1 in their opening match of the Premier League season on Saturday, while Baines and Fellaini both played as Everton drew 2-2 with Norwich.
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