The Daily Mail says Championship duo Ipswich and Swansea have also made enquiries about the 21-year-old who has been at Stamford Bridge for five years but made just one top-flight start.
Sinclair was on loan at Wigan last season, making 22 first-team appearances but only five in the starting line-up.
Holloway, who also tried to sign Sinclair in February 2008 when he was in charge at Leicester, has been quiet in the transfer market since the Tangerines won promotion.
But he is hoping the fact that he has worked with Sinclair previously will help him to complete a deal in time for the big kick-off on Saturday week.
Another reason why Sinclair is likely to prefer to relocate to the north west is that his girlfriend, Coronation Street star Helen Flanagan, is based there.