The 28-year-old midfielder saw his 2012/13 campaign cut short in December for the second consecutive season after he continued to be blighted by ulcerative colitis, and underwent another operation back in April.
After his enforced break, Fletcher is said to be making a slow, but promising recovery, aided by a diet programme which is aimed to help the Scotland international bulk up having lost a considerable amount of weight.
The news will be a huge boost to new Manchester United manager David Moyes, who is known to be a huge admirer of Fletcher, having tried to sign him during his time at Everton.
Red Devils fans might not have expected to ever see the midfielder pull on a Manchester United shirt again, but all going well, Fletcher could make his Old Trafford return by the start of the new season.
Sir Alex Ferguson paid tribute to Fletcher during his farewell speech to supporters after his 1500th and final game in charge at Old Trafford.
But, with two years still to run on his Manchester United contract, Fletcher will be hoping to add to the 10 appearances he made last season, and has set his sights on a return to first-team action in time for pre-season training next month.