Young is currently battling his way back to fitness after undergoing surgery on his groin in May, and it was thought it would be October at the earliest before he was ready to return to action.
However, he is reported to have played in a full-contact six-a-side practice match at the weekend, which would suggest he is close to making a return, news which is said to have alerted Chelsea.
The Blues are looking to bolster their quota of homegrown players and are already targeting moves for Arsenal's Alex Oxlade-Chamberlain and Leicester City midfielder Danny Drinkwater, and Young can now be added to that list.
Young was linked with a move away from Old Trafford last season and at the time Reds boss Jose Mourinho spoke of his influence in the dressing room and how he would be reluctant to let him move on.
There would be no shortage of interest in the former Aston Villa star if he did become available, but Chelsea would feel confident of fighting off the competition to wrap up a deal.