The Egyptian-born Qatari, who joined Zamalek in January after terminating his deal with their arch-rivals Ahli, stole the show with an energetic display to help the Cairo giants secure their eighth successive win.
He was unlucky not to score on two occasions before central defender Mahmoud Fathallah headed home to make amends and give Zamalek a precious victory.
Yasser was eventually given the best player award.
"I want to thank Yasser tonight," Hassan, who turned around the team's fortunes after taking the helm in November last year, said after the game.
"He produced superb displays in two consecutive games despite lacking match fitness (having been out of favor with Ahli).
"All the players played very well, including youngster Omar Gaber who was not affected by the pressure of making his debut."
Zamalek moved up to second in the league table to keep alive their hopes of competing for a title they last won in 2004.
They are seven points behind leaders Ahli, who are chasing a sixth consecutive triumph.
Gaish, who boast two powerful strikers in Ernest Papa Arko and Mikael Dogbe, had been hoping to break into the top four at the expense of Zamalek.
However, they wasted some clear-cut opportunities in the first half to remain sixth on 30 points from 20 games.
"We relied on counter attacks but we couldn't make the most of them," Gaish coach Farouk Gaafar said.
"We should have converted the three goalscoring chances we had in the first half."