CAIRO — When Mohamed Salah is on the offensive, you better watch out.

That’s the lesson countless soccer opponents have learned from Mr. Salah, Egypt’s goal-scoring maestro and sports superstar. But this week Mr. Salah trained his devastating focus on a new target: the bungling bosses of Egypt’s national soccer association.

In a blistering series of Twitter messages, video posts and leaked letters, Mr. Salah, 26, vented a summer’s worth of frustrations against the leadership of the Egyptian Football Association for what he called its grossly incompetent handling of Egypt’s short-lived World Cup campaign in Russia in June.

Autograph hunters were permitted to knock on Mr. Salah’s hotel door in the middle of the night, he said, while preening Egyptian celebrities barged in on him, invading his personal space. On long plane journeys, players traveled in economy class while their managers stretched out in business-class seats. Mr. Salah, who also plays for the English club Liverpool, couldn’t even make it to the breakfast buffet without being swamped by fans.

A good soccer association ensures that its players are relaxed, Mr. Salah noted on Twitter. “But in reality, I don’t see anything but the opposite,” he added.