'He has won games for us so the fact that he missed is not a problem.'
Houllier, who will be without Emile Heskey (back), Florent Sinama-Pongolle (ankle), Vladimir Smicer (Achilles) and Salif Diao (calf) against the Bulgarians, believes his players can bounce back from the defeat on the south coast.
But only a victory against Sofia - beaten just once all season in domestic competition - will appease Liverpool's angry public.
A defiant Houllier said: 'We will keep strong and finish even stronger, I can assure you of that. I trust my players. That is the main thing.
'They are upset and hurt by what has happened. And at some stage a team has got to pay for our frustration. We will make sure that what is said and what is written does not affect us.
'When you work you are not really bothered about criticism. Obviously the result was not what we expected at Portsmouth, but I do not accept we did not deserve to go through. We will live with that.'
But the levels of criticism have reached massive proportions since the Pompey chimes tolled Liverpool's Cup exit.
Houllier said: 'What is going on off the pitch we are aware of, but we must make sure it does not affect what is happening on the pitch.
'This is our last chance of silverware, and I know we will give it our best shot right to the end of the season, as well as in the league.
'We are obviously disappointed after Portsmouth. Beforehand we had lost only one of the previous 12. We were improving and playing better.
'But I am still confident. We have got Milan Baros back fit now and I think that second half performance from him at Portsmouth showed how much we had missed him. I understand the frustration around the cup result, and it is shared from within our camp.'
Liverpool v Levski Sofia, Anfield, tonight, 8pm, live on Channel Five
