The 28-year-old's second-half introduction in February's Bundesliga clash at Kaiserslautern only lasted for eight minutes as he received a fierce blow to the chest in the 1-1 draw.

Shortly after the game, the Egypt forward said a scan had showed that his injury was not serious.

Further examinations proved he's nursing more than just a negligible contusion. However, he still has a chance to be fit for Egypt's Nations Cup qualifier with South Africa in March.

"I guess ten days (after reaching full recovery) would be enough for me to get ready for a comeback," Zidan told the Egyptian FA's official website.

"I even think I could be able to take part in a league match with Dortmund before the South Africa meeting."

According to doctors, his injury could take up to three weeks to heal.

Zidan has only appeared twice for Bundesliga leaders Dortmund so far this season as he spent most of last year on the sidelines after damaging his cruciate ligament in April 2010.