Defender Karim Zekri has become the fourth player to leave Zamalek in January after joining Egyptian league surprise package Petrojet, the Cairo giants announced on Saturday. "Zekri moved to Petrojet on a permanent basis," Zamalek said in a statement on their official website, without disclosing the transfer fee or the duration of the contract. Petrojet, who lie second in the league table, were keen on strengthening their shaky defense, which leaked 18 goals in 15 games. They failed in their attempt to lure Ahli defender Rami Adel, who eventually joined Masri. But Petrojet made use of the January transfer window to land Zekri, who has been a peripheral figure at Zamalek since joining from Masri in the summer of 2007. The 23-year-old follows in the footsteps of Mohamed Ibrahim, Ayman Abdul-Aziz and Mostafa Gaafar. Midfield duo Ibrahim and Abdul-Aziz joined Gaish and Konyaspor on loan respectively while Gaafar penned a four-and-a-half year deal with ENPPI. Meanwhile, Zamalek announced that Ahmed Tharwat, who plays for second-division side Rabat and Anwar, will be joining the club next season. The White Knights were looking to sign the midfielder before the closure of the transfer window but couldn't reach an agreement with his club. They consequently decided to sign him when his contract expires in the summer.