Israeli Judo Olympic champion Or Sasson won a swift victory over Islam El Shehaby Friday, knocking his Egyptian opponent flat on his back.

WATCH: Israeli Or Sasson beats Egypt’s Islam El Shehaby in #Judo #Rio2016 #Olympics pic.twitter.com/3nh6h0UA2e

— Zionist Federation (@ZionistFed) August 12, 2016

Following his victory, Sasson extended his hand to El Shehaby. But what happened next garnered loud boos from a crowd of Olympic spectators in Rio.

In an overt display of poor sportsmanship, El Shehaby refused Sasson's gesture.

Egyptian judoka Islam El Shehaby loses to Israeli Or Sasson, refuses to shake hands in a major breach of etiquette. pic.twitter.com/kOU1oAd5YW

— Zaid Benjamin (@zaidbenjamin) August 12, 2016

Now people are calling the Egyptian fighter a “pathetic excuse” for an Olympian.

After the match, El Shehaby, 34, was summoned back to the mat by the referee, who demanded that he bow. The ultraconservative Salafi Muslim fighter gave a quick nod before exiting.

El Shehaby was reportedly pressured before the Games from Islamist activists in Egypt to withdraw from the first-round heavyweight bout against Sasson.

Sasson, 25, advanced to the semifinals, where he lost to eventual champion Teddy Riner of France. He walked away with a bronze medal.

Later, Sasson told the Associated Press that his coaches had warned him that El Shehaby might refuse to shake his hand even though the two had never fought before.

"I knew he would do it, so it wasn't a surprise for me," he said. "But I cannot say anything. This was his decision."

El Shehaby refused to comment on the incident.