Why did the Yankees wear a black mourning band around their sleeve? This is usually done when someone has died. If so, who died?

The New York Yankees wore black armbands on their uniforms last season to honor the memory of Bob Lemon. Lemon was a Hall of Fame pitcher for the Cleveland Indians, compiling a 207-128 won-loss record for them in 15 seasons. After retiring, he went on to manage the Yankees to the World Series title in 1978 and led them to another World Series in 1981, where they lost to the Los Angeles Dodgers. Lemon died from a stroke on January 11, 2000, after several years of failing health.