كتب : وكالات
The Qatar forward already missed Friday's session before his lawyer and spokesman Hesham Hassan confirmed why the 28-year-old went AWOL.
But Yasser's disappearance caused Zamalek to be in a state of disarray that does not seem to be leading to any agreement between both parties.
Football director Ibrahim Hassan stressed that Yasser's decision to boycott training will only result in 'severe punishment'.
"Yasser will be handed severe punishment for missing training without prior notice," Hassan told FilGoal.com.
"This is not a professional way to sort things out, it just indicates that he doesn't respect the team.
"He needs to learn that he can't force us to do anything."
Hesham said his client wants to earn EGP 2.5 million at Zamalek, which is the same worth of his contract with former club Ahli.
Yasser had landed himself in hot water earlier this season when he did not report back from international duty on time.
He later rejected a contract extension from Zamalek, to raise doubts over his commitment to the Whites.