The Qatari was injured in the Gulf Cup of Nations, where his nation was eliminated from the semis by hosts Oman.

Ahli's official site stated that the 26-year-old will have scans on Saturday, after which his injury extent will be determined.

Yasser is clearly doubtful for Monday's encounter against Harras Hodoud in Alexandria.

Meanwhile, long-term absentee Emad Al-Nahhas will fly to Portugal in midweek, as part of his rehabilitation program.

The veteran defender had an anterior cruciate ligament operation late in 2008 for the second time in two years.

Al-Nahhas is unlikely to feature again this season, but was registered in Ahli's African Champions League squad.