كتب : Hatem Maher
Mohamed Salah left Tersana by mutual consent following the team's 1-0 defeat to Gaish on Sunday.
Former Ittihad tactician Omar, who has a plenty of experience in managing Egyptian top-flight clubs, took over from Salah.
Tersana impressed in their first match under Omar's guidance, brushing aside Alexandria-based club Olympic.
Midfielder Heidar Abou-Bakr opened the scoring in the 35th minute with a low shot from outside the area.
Olympic had Wakil Salama dismissed on the hour mark for a second bookable offense.
Tersana made the most of their numerical advantage to score three goals in the second half.
Talaat Moharam doubled their lead in the 75th minute when he connected with Abou-Bakr's pinpoint cross to head home.
Defender Sayed Abdul-Moghni added the third two minutes from time before diminutive midfielder Hani Hassan completed the rout in stoppage time.
The victory lifted Tersana off the bottom of the 16-team table. They lie 15th on 10 points, one behind Olympic.
Asyut Petroleum fell to the bottom after slumping to a 2-0 defeat to Police Union, who chalked up their second successive win following their stunning victory over Ismaili last week.
Two goals from Mohamed Yehia and Violete Armand either side of the interval gave Police all three points.