Doryoku wa kanarazu mukuwareru. Moshi mukuwarenai doryoku ga aru no naraba, sore wa mada doryoku to wa yobenai. “Effort is always rewarded. If there is effort that is not rewarded, it cannot yet be called effort.”
Japanese websites often print these words as a saying of the baseball player Ō Sadaharu. The site All About calls it his best-known saying. Neither of the two sites checked here names the occasion or gives an original source, so the attribution is not confirmed.