Martin O'Neill has described it as a 'massive blow' for the club, as Hartson has scored vital goals in the UEFA Cup this season.
Although he is going to be a big miss, it solves a problem for Martin O'Neill, who will now look to Chris Sutton to partner Henrik Larsson up-front.
Hartson has been suffering from a back problem for months now, and will be devastated at being ruled out of the final.