Houllier feels that Kewell's troublesome ankle problems, which forced him out of Australia's midweek trip to Venezuela, should be boosted by a break from first-team action.
Houllier said: "I think missing this game couldn't have come at a better time for Harry. He hasn't been able to complete the last two matches because he is still feeling his ankle.
"He couldn't go with the Australian team to Venezuela. He wanted to play but knowing he was suspended for Sunday it was an opportunity for him to rest. His ankle is not right so the rest will probably be extremely beneficial to him."