كتب : وكالات
The promoted side were undone by a first-half header from defender Vincent Euvrard.
Lierse's Egyptian winger Mohamed Abdul-Wahed missed the game due to an injury while his compatriot Ahmed Samir was left out of the team's squad for no apparent reason.
Fellow Egyptian Mohamed Al-Gabbas started on the bench before being introduced in the 35th minute.
His pinpoint cross from the right four minutes after his introduction found Canadian striker Tomasz Radzinski, whose header struck the post.
Al-Gabbas almost leveled the score when he broke clear of defense on 51 minutes but his low shot was blocked by the keeper.
Emad Meteb's Standard Liege were held to a 1-1 home draw by Zulte-Waregem on Friday.
The Egyptian striker was absent because he is yet to recover from a back injury.