Fellow Egyptian Mohamed Abdul-Wahed set up Canadian 36-year-old striker Tomasz Radzinski for Lierse's opener after 20 minutes.

Al-Gabbas, who ended his goal drought, doubled their advantage 14 minutes later after heading home a cross from Radzinski.

Matters went from bad to worse for Tournai when they had defender Patrick Barul sent off for a second bookable offense.

Substitute Peter Kovacs made it 3-0 four minutes past the hour mark and Al-Gabbas completed the rout 10 minutes later.

Tournai scored a consolation through Duquesnoy with two minutes remaining.

"I'm very happy with the two goals, those are my first two goals this season," former Masri striker Al-Gabbas said in an interview with Lierse's TV channel after the game.

"I have lots of problems - sometimes I play on the right, sometimes I play on the left and sometimes I play as a striker.

"I was trying my best to score, it's my first start for five or six games. I was on the bench during the past matches.

"I always try to do my best whenever I play even If I play 5 or 10 minutes," he added.

Lierse's next opponents in the cup will be determined by a draw as they eye a consolation in Belgium's secondary competition after a poor league run.

The four-time Belgian champions, who are owned by Egyptian businessman Maged Sami, lie third from bottom in the league table with 9 nine points from 14 games.