The 24-year-old winger last featured against Stevenage in the fifth round replay at White Hart Lane and remains sidelined.
Harry revealed that Emmanuel Adebayor also has a hamstring problem and might not feature against Owen Coyle's team.
"We're still waiting to see, we've got one or two knocks. Adebayor has a little bit of a hamstring problem so we'll wait and see how he is," the manager told his pre-match press conference on Friday.
"Aaron Lennon is still out with his hamstring injury, so there's one or two little knocks but we'll see how we are this morning."