The striker was injured in the fifth minute of our 6-0 victory in the FA Cup quarter-final at the Lane.
Harry let fly from the right angle of the goal but went over as Millwall defender Jay Cooper slid in attempting to block his shot.
Having got to his feet after treatment, he walked steadily around the pitch before disappearing straight back down the tunnel.
“We need to wait now to assess him and after a scan we’ll know how his ankle is,” explained Mauricio. “It’s disappointing but we have to wait and try to be positive.”