Houllier, despite admitting that the 30-year-old Pole was dropped for the weekend fixture at the Riverside and not rested as was first suggested, insists that Dudek still has a part to play in his plans for the club.
Houllier, speaking to the club's official website, said: Jerzy Dudek is not for sale. If every time a player was dropped he was for sale, we would end up with about six players in our squad.
"We have just lost Steve Finnan to injury, with Jamie Carragher already out injured and Markus Babbel and Gregory Vignal out on loan. That should teach us a lesson."