كتب : Hatem Maher
Hassan broke the deadlock in the 38th minute after he received Nicolas Frutos' pass on the edge of the area before firing a low shot into the right bottom corner of the net.
The in-form midfielder doubled the lead seven minutes after re-start when he volleyed home from the rebound after Mohamed Tchite's initial effort was saved by Lierse keeper.
Five minutes from time, Anderlecht were awarded a penalty after Tchite was obstructed in the area.
Hassan stepped-up but the keeper denied his first hat-trick attempt.
The victory placed Anderlecht as joint leaders with Racing Genk on 23 points each but the latter will play Sint-Truiden on Sunday.