MIAMI — In an effort to revitalize their long-struggling franchise and attract the Latino baseball fans of South Florida, the Miami Marlins built a new $634 million stadium, revamped their uniforms, signed one of the biggest Hispanic stars in the league and hired a brash manager from Venezuela who guided the Chicago White Sox to a World Series title. The team even made sure its electronic concessions menus alternated between English and Spanish.

Then the manager, Ozzie Guillen, known as much for his incendiary comments as his baseball savvy, said the one thing that could repel the Cuban-American community that the team had earmarked as its fan base. He said he admired and respected the longtime Cuban dictator Fidel Castro.

Just a week into the baseball season, with Mr. Guillen and the Marlins under intensifying pressure from Cuban-American organizations and local politicians, the team suspended its manager for five games Tuesday. Mr. Guillen left his team in Philadelphia to hold a news conference at the Marlins’ new stadium, where he apologized for what he called embarrassing remarks made in a Time magazine article.

“This is the biggest mistake I’ve made in my life so far,” he said. “I was very stupid, very naïve about the comment.”